微生物英文文献及翻译—翻译资料
微生物专题英文文献
班级：生物工程 学生：马春玲 2013年12月13日
LOGO
试验内容
1. Purpose and meaning 2. Introduction 3. Materials and methods
4.5 正交试验结果
Table 5. Results of ortho.1 Trend curve
Fig.2 Relationship between xylanase and time of fermentation in Aspergillus niger N212
通过对出发菌株注入不同剂量的氮离子，低能氮离子 束对菌体细胞均有一定程度的致死和损伤作用，细胞及其 损伤DNA又在其修复系统的作用下得到不同程度的修复， 从而导致黑曲霉孢子的存活率先下降，后上升，然后又下 降，并且菌种的修复出错会使其突变率大大提高，从而提 高了菌株的正突变率，从而确定了氮离子最佳注入参数。 以上试验可以得出最优培养基的组成（即各组分的最 适浓度），而且在以上培养得到了黑曲霉N212（表2），当 它发酵60个小时后酶活达到600IU/ml，比之前未优化的菌 株减少了12个小时，而且相对于原出发菌株酶活增加了100 ％。 试验证明离子注入对微生物进行诱变改良是一种行之 有效的诱变技术。
木聚糖酶是植物细胞壁的主要之一，属 于非淀粉多糖。可作为生物漂白剂用于造纸工 业，也可用于生物转化等等。目前木聚糖酶的 生产主要还依靠真菌。
对于产酶微生物的育种，国外多采用基因工程手段 构建高产菌，而国内多采用传统的诱变方法，如紫外辐 射、化学诱变剂处理等，这些诱变手段获得的突变株一 般稳定性差、容易产生回复突变且负突变较多及诱变选 育的工作量很大，而20世纪80年代末，人们发现离子束 可以引起靶物质原子移位和重排，使细胞表面刻蚀和穿 孔，并能影响和改变细胞电性等现象，提出了离子束可 以用于细胞加工和基因转移的设想，并陆续得到了研究 证实，由此产生了国内外普遍关注的离子束生物技术工 程学，而且离子束育种是一项具有我国自主知识产权且 被国际所承认的定向遗传改良的集物理诱变和化学诱变 于一身的综合诱变方法，具有损伤小、突变谱广、突变 率高的特点。
微生物学细菌中英翻译及促生素概论
清酒乳杆菌(Lactobacillus sakei),弯曲乳杆菌(Lactobacillus curvatus),明串珠菌属的肠膜明串珠菌(Leuconostoc mesenteroides)和非培养的明串珠菌(Uncultured Leuconostoc sp.)清酒乳杆菌清酒亚种(Lactobacillus sakei subsp.sakei)弯曲乳杆菌蜜二糖亚种(Lactobacillus curvatus subsp.melibiosus)粪肠球菌（E.faecalis）屎肠球菌（E.faecium)鸟肠球菌(E.avium) 酪黄肠球菌(E.casseliflavus)坚忍肠球菌(E.durans) 鸡肠球菌E.galinarum)芒地肠球菌(E.mundii) 恶臭肠球菌(E.maladoratum)希拉肠球菌(E.hirae) 孤立肠球菌（E.solitarius）棉子糖肠球菌(E.raffinosus) 假鸟肠球菌(E.pseudoavium)粪肠球变异株(E.faecalis var)。
Abiotrophia adjacens 毗邻贫养菌Abiotrophia defectiva 软弱贫养菌Achromobacter spp 无色杆菌属某些种Acinetobacter /Pseudomonas spp 不动杆菌/假单胞菌属某些种Acinetobacter baumannii 鲍氏不动杆菌Acinetobacter calcoaceticus 醋酸钙不动杆菌Acinetobacter haemolyticus 溶血不动杆菌Acinetobacter johnsonii 约氏不动杆菌Acinetobacter junii 琼氏不动杆菌Acinetobacter lwoffii 鲁氏不动杆菌Acinetobacter radioresistens 抗辐射不动杆菌Acinetobacter spp 不动杆菌属某些种Acinetobacter spp/Pseudomonas spp 不动杆菌属某些种/假单胞菌属某些种Acinetobacter/Pseudomonas spp 不动杆菌/假单胞菌属某些种Actinobacillus actinomycetemcomitans 伴放线放线杆菌Actinomyces israelii 衣氏放线菌Actinomyces meyeri 麦氏放线菌Actinomyces naeslundii 内氏放线菌Actinomyces neuii anitratus 纽氏放线菌无硝亚种Actinomyces neuii neuii 纽氏放线菌纽氏亚种Actinomyces neuii radingae 纽氏放线菌罗亚种Actinomyces neuii turicensis 纽氏放线菌图列茨亚种Actinomyces odontolyticus 龋齿放线菌Actinomyces viscosus 粘放线菌Aeromonas caviae 豚鼠气单胞菌Aeromonas hydrophila 嗜水气单胞菌Aeromonas hydrophila gr．嗜水气单胞菌群Aeromonas salmonicida achromogenes 杀鲑气单胞菌无色亚种Aeromonas salmonicida masoucida 杀鲑气单胞菌杀日本鲑亚种Aeromonas salmonicida salmonicida 杀鲑气单胞菌杀鲑亚种Aeromonas sobria 温和气单胞菌Agrobacterium radiobacter 放射形土壤杆菌Alcaligenes denitrificans 反硝化产碱菌Alcaligenes faecalis 粪产碱菌Alcaligenes spp 产碱菌属某些种Alcaligenes xylosoxidans 木糖氧化产碱菌Alloiococcus otitis 耳炎差异球菌Anaerobiospirllum succiniproducens 产琥珀酸厌氧螺菌Arachnia propionica 丙酸蛛菌Arcanobacterium bernardiae 伯纳德隐秘杆菌Arcanobacterium haemolyticum 溶血隐秘杆菌Arcanobacterium pyogenes 化脓隐秘杆菌Arcobacter cryaerohoilus 嗜低温弓形杆菌Arthrobacter spp 节杆菌属某些种Debaryomyces polymorphus 多形德巴利酵母菌Dermabacter hominis 人皮肤杆菌Dermacoccus nishinomiyaensis 西宫皮肤球菌Dietzia spp 迪茨菌属某些种Edwardsiella hoshinae 保科爱德华菌Edwardsiella tarda 迟钝爱德华菌Eikenella corrodens 啮蚀艾肯菌Enterobacter aerogenes 产气肠杆菌Enterobacter amnigenus 河生肠杆菌Enterobacter asburiae 阿氏肠杆菌Enterobacter cancerogenus 生癌肠杆菌Enterobacter cloacae 阴沟肠杆菌Enterobacter gergoviae 日沟维肠杆菌Enterobacter intermedius 中间肠杆菌Enterobacter sakazakii 阪崎肠杆菌Enterobacter spp 肠杆菌属某些种Enterococcus avium 鸟肠球菌Enterococcus casselifavus 铅黄肠球菌Enterococcus durans 耐久肠球菌Enterococcus faecalis 粪肠球菌Enterococcus faecium 屎肠球菌Enterococcus gallinarum 鹑鸡肠球菌Enterococcus saccharolyticus 解糖肠球菌Erwinia spp 欧文菌属某些种Erysipelothrix rhusiopathiae 猪红斑丹毒丝菌Escherichia coli 大肠埃希菌Escherichia fergusonii 费格森埃希菌Escherichia hermannii 赫氏埃希菌Escherichia vulneris 伤口埃希菌Eubacterium aerofaciens 产气真杆菌Eubacterium lentum 迟缓真杆菌Eubacterium limosum 粘液真杆菌Ewingella americana 美洲爱文菌促生素：概论简介发酵乳形态的促生素历史要追溯回数千年前，但直到本世纪初期才根据科学原理进行科学性研究。
微生物翻译
微生物翻译1(总1页)--本页仅作为文档封面，使用时请直接删除即可----内页可以根据需求调整合适字体及大小--微生物翻译2919尹炫植SynopsisMicrobiology is the study of microorganisms, which are tiny organisms too small to be seen without the aid of a microscope. The family of microorganisms includes prokaryotes, eukaryotes, and viruses. In general, microorganisms are small, simple, organisms that grow rapidly. Prokaryotes are single-cell organisms, such as bacteria, that have no real nucleus and do not contain membrane-enclosed organelles. Eukaryotes, such as algae, fungi and protozoa, have a real nucleus and membrane-enclosed organelles. Viruses are tiny, complex molecules composed of protein and nucleic acid, that cannot replicate independently off their host cells.The study of microbiology provides an excellent foundation for understanding cell function in higher organisms. Knowledge of microbiology is necessary in problem-solving and dealing with practical issues in medicine, agriculture, industry, and environmental studies.In this chapter we will introduce the study of microbiology as a scientific discipline and review the major historical developments in the field. The chapter concludes with a discussion of the important role that microbiology plays in the life sciences.微生物学是研究不借助显微镜看不到的微小的生物学科。
微生物英文文献及翻译—翻译
A/O法活性污泥中氨氧化菌群落的动态与分布摘要：我们研究了在厌氧—好氧序批式反应器（SBR）中氨氧化菌群落（AOB）和亚硝酸盐氧化菌群落（NOB）的结构活性和分布。
在研究过程中，分子生物技术和微型技术被用于识别和鉴定这些微生物。
污泥微粒中的氨氧化菌群落结构大体上与初始的接种污泥中的结构不同。
与颗粒形成一起，由于过程条件中生物选择的压力，AOB的多样性下降了。
DGGE测序表明，亚硝化菌依然存在，这是因为它们能迅速的适应固定以对抗洗涤行为。
DGGE更进一步的分析揭露了较大的微粒对更多的AOB种类在反应器中的生存有好处。
在SBR反应器中有很多大小不一的微粒共存，颗粒的直径影响这AOB和NOB的分布。
中小微粒（直径<0.6mm）不能限制氧在所有污泥空间的传输。
大颗粒（直径>0.9mm）可以使含氧量降低从而限制NOB的生长。
所有这些研究提供了未来对AOB微粒系统机制可能性研究的支持。
关键词：氨氧化菌（AOB），污泥微粒，菌落发展，微粒大小，硝化菌分布，发育多样性1.简介在浓度足够高的条件下，氨在水环境中对水生生物有毒，并且对富营养化有贡献。
因此，废水中氨的生物降解和去除是废水处理工程的基本功能。
硝化反应，将氨通过硝化转化为硝酸盐，是去除氨的一个重要途径。
这是分两步组成的，由氨氧化和亚硝酸盐氧化细菌完成。
好氧氨氧化一般是第一步，硝化反应的限制步骤：然而，这是废水中氨去除的本质。
对16S rRNA的对比分析显示，大多数活性污泥里的氨氧化菌系统的跟ß-变形菌有关联。
然而，一系列的研究表明，在氨氧化菌的不同代和不同系有生理和生态区别，而且环境因素例如处理常量，溶解氧，盐度，pH，自由氨例子浓度会影响氨氧化菌的种类。
因此，废水处理中氨氧化菌的生理活动和平衡对废水处理系统的设计和运行是至关重要的。
由于这个原因，对氨氧化菌生态和微生物学更深一层的了解对加强处理效果是必须的。
当今，有几个进阶技术在废水生物处理系统中被用作鉴别、刻画微生物种类的有价值的工具。
【推荐】关于微生物部分英文翻译-范文模板 (2页)
【推荐】关于微生物部分英文翻译-范文模板本文部分内容来自网络整理，本司不为其真实性负责，如有异议或侵权请及时联系，本司将立即删除！== 本文为word格式，下载后可方便编辑和修改！ ==关于微生物部分英文翻译微生物的英文：microorganism参考例句：microbial insecticide微生物杀虫剂microbial transformation of steroids甾体的微生物转化Microorganisms have a wide taxonomic distribution.微生物在分类学上的分布是很广泛的。
A microorganism,especially a pathogen.一种微生物，尤指病原体Microorganisms have a wide taxonomic distribution.微生物在分类学上的分布是很广泛的。
We can expect to continue hearing of many new advances in work with this organism.我们期待着继续听到有关这种微生物的最新研究进展。
Modern medicine owes a great deal to the discovery of certain tiny disease-carrying organisms.某些传染疾病的微生物的发现，对现代医学的发展作出了巨大的贡献。
A single - celled microorganism,especially a flagellate protozoan of the genus Monas.单胞体单细胞的微生物，尤指单胞虫类的有鞭毛的原生动物A polypeptide antibiotic,produced by the soil microorganism Bacillus brevis,that is a major constituent of tyrothricin.短杆菌酪素一种多肽抗生素，由土壤中的微生物土壤杆菌产生，是混合短杆肽菌的重要组成部分food - borne poisoning microorganism。
微生物英文文献及翻译—原文
微生物英文文献及翻译—原文本期为微生物学的第二讲，主要讨论炭疽和蛔虫病这两种既往常见而当今社会较为罕见的疾病。
炭疽是由炭疽杆菌所致的一种人畜共患的急性传染病。
人因接触病畜及其产品及食用病畜的肉类而发生感染。
临床上主要表现为皮肤坏死、溃疡、焦痂和周围组织广泛水肿及毒血症症状；似蚓蛔线虫简称蛔虫，是人体内最常见的寄生虫之一。
成虫寄生于小肠，可引起蛔虫病。
其幼虫能在人体内移行，引起内脏幼虫移行症。
案例分析Case 1：A local craftsman who makes garments from the hides of goats visits his physician because over the past few days he has developed several black lesions on his hands and arms. The lesions are not painful, but he is alarmed by their appearance. He is afebrile and his physical examination is unremarkable.案例1：一名使用鹿皮做皮衣的当地木匠来就医，主诉过去几天中手掌和手臂上出现几个黑色皮肤损害。
皮损无痛，但是外观较为骇人。
患者无发热，体检无异常发现。
1. What is the most likely diagnosis?Cutaneous anthrax, caused by Bacillus anthracis. The skin lesions are painless and dark or charred ulcerations known as black eschar. It is classically transmitted by contact with thehide of a goat at the site of a minor open wound.皮肤炭疽：由炭疽杆菌引起，皮损通常无痛、黑色或称为焦痂样溃疡。
微生物和细菌英语作文
微生物和细菌英语作文（中英文版）Microorganisms and bacteria are tiny organisms that are not visible to the naked eye.They are present everywhere, including in the air, water, soil, and even inside our bodies.Although they are small, they play a crucial role in various biological processes.微生物和细菌是肉眼无法看到的微小生物。
它们存在于空气中、水中、土壤中，甚至存在于我们体内。
尽管它们体积很小，但在各种生物过程中起着关键作用。
One of the most important roles of microorganisms is in the decomposition of organic matter.They break down dead plants and animals into simpler substances, which are then used by other organisms as nutrients.This process is known as decomposition and is essential for the recycling of nutrients in ecosystems.微生物最重要的作用之一是在有机物的分解中。
它们将死亡的植物和动物分解成更简单的物质，然后这些物质被其他生物作为营养素使用。
这个过程被称为分解，对于生态系统中营养素的循环至关重要。
In addition to decomposition, microorganisms also play a key role in the nitrogen cycle.Some bacteria have the ability to convert atmospheric nitrogen into a form that can be used by plants.This process, known as nitrogen fixation, is essential for plant growth and the production of food crops.除了分解作用外，微生物在氮循环中也起着关键作用。
有关微生物的英语作文
有关微生物的英语作文英文回答：Microorganisms are a diverse group of organisms that include bacteria, viruses, fungi, and protozoa. They are found in all environments on Earth, from the deepest oceans to the highest mountains. Microorganisms play a vital role in the cycling of nutrients, the decomposition of organic matter, and the production of oxygen. They are also responsible for a wide range of human diseases, from the common cold to tuberculosis.The study of microorganisms is called microbiology. Microbiologists use a variety of techniques to study microorganisms, including microscopy, culturing, and molecular biology. Microscopy allows microbiologists to visualize microorganisms and study their morphology. Culturing allows microbiologists to grow microorganisms in the laboratory and study their growth and metabolism. Molecular biology allows microbiologists to study thegenetic material of microorganisms and understand how they function.Microorganisms have a wide range of applications in industry, medicine, and agriculture. In industry, microorganisms are used to produce a variety of products, including antibiotics, enzymes, and biofuels. In medicine, microorganisms are used to develop vaccines and antibiotics. In agriculture, microorganisms are used to improve soil fertility and crop yields.The study of microorganisms is essential for understanding the role they play in the environment and for developing new ways to use them to benefit humanity.中文回答：微生物是一个多样化的生物群，包括细菌、病毒、真菌和原生动物。
微生物英文文献
Results
二、分子鉴定
(1) Pca-QS-0-1, Pch-QS-0-3, and Pe-QS-0-1;
Results
二、分子鉴定
(5) Pv-QS-0-1;
Results
Two new ITS-5.8S rDNA sequence types
(1) Cl-QS-0-1 and Cl-QS-0-2 are two new anamorph species in the genus Tulasnella. (2) Pv-QS-0-1 did not show high homology with high Sequence
成 苗
碳 源 种子发芽
Many fungi isolated from mycorrhizal orchid roots have been classified as Rhizoctonia or Rhizoctonia-like
fungi.
Plant materials
B. Why 27种is Rhizoctonia-like Fungi？
Molecular characterization
Homogenizing
PCR Purifing Sequencing
样品均匀 扩增
纯化 基因测序
Sequence analysis
Results
一、形态学
(1) Pca-QS-0-1, Pch-QS-0-3, and Pe-QS-0-1; (2) D1-KT-TC-1 and C3-DT-TC-2; (3) Pv-QS-0-2 and Df-QS-3-1;
Orchids rely on the infection of Rhizoctonia-like fungi
微生物学术语双语（中英文）对照
微生物学术语双语（中英文）对照Brock Biology of Microorganisms Bilingual Glossary（For Internal Circulation Only）微生物学术语双语（中英文）对照北京林业大学生物科学与技术学院微生物教研室谢响明2007年6月10日Catalogue目录Chapter1 Microorganisms and MicrobiologyChapter 2 An Overview of Microbial LifeChapter 3 MacromoleculesChapter 4 Cell Structure/FunctionChapter5 Nutrition, Laboratory Culture, and Metabolism of MicroorganismsChapter 6 Microbial GrowthChapter 7 Principles of Microbial Molecular Biology Chapter 8 Regulation of Gene ExpressionChapter 9 Essentials of VirologyChapter 10 Bacterial GeneticsChapter 11 Microbial Evolution and Systematics Chapter 15 Microbial GenomicsChapter 18 Methods in Microbial EcologyChapter 19 Microbial Habitats, Nutrients Cycles Chapter 20 Microbial Growth ControlBilingual Glossary for MicrobiologyChapter 1Landmark：里程碑Ramifications：分支non-cellular life ：非细胞生命prion：朊病毒microbial diversity and evolution：微生物的多样性和进化pathogens：病原体genetic engineering：基因工程entity：实体macromolecules：大分子Reproduction：繁殖Differentiation：分化Communication：信息沟通coding devices：编码机制attributes：特征，品质coordination.：协调regulation：调节optimally attuned to最适地调和populations：种群habitat.：生境assemblages：集合体microbial communities：微生物群落biofilms：生物被膜hot springs：温泉Aquatic：水生的Terrestrial：陆生的Prokaryotic cells：原核细胞ecosystem ：生态系统biomass：生物量nitrogen：氮phosphorus：磷Bubonic Plague：鼠疫Fleas：跳蚤Mortality：死亡率Grotesque：奇异Liquefy：液化Influenza and pneumonia：流感和肺炎Tuberculosis：肺结核spontaneous generation：自然发生学说microbes：微生物Broth：肉汤Flask：烧瓶Guncotton filters：棉花滤器Dissolved：溶解的Ether：醚Particles：微粒flask with swan neck：曲颈瓶sterilization：灭菌vaccines：疫苗anthrax：炭疽热fowl cholera：禽流感rabies：狂犬病Germ theory：病菌说Koch’s postulates：科赫假设(法则) contagious diseases：传染病artificially infected animals：人工感染的动物Solid medium：固体培养基Gelatin：明胶Agar：琼脂Colony formation：菌落形成Differential staining：鉴别染色Pure culture：纯培养isolation：分离, 隔离inoculation：接种Tuberculin：结核菌素Diagnosis：诊断Subdisciplines：（学科的）分支enrichment culture：富集培养aerobic：需氧的N-fixing bacteria：固氮细菌sulfate-reducing：硫酸盐还原sulfur-oxidizing bacteria：硫氧化细菌root nodule：根瘤Lactobacillus：乳酸杆菌tobacco mosaic virus：烟草花叶病毒tenets：原则virology：病毒学nitrifying bacteria：硝化细菌nitrification：硝化作用oxidation of ammonia to nitrate：从氨氧化为硝酸盐hydrogen sulfide：硫化氰chemolithotrophy：无机化能营养型autotrophs：自养生物anaerobe ：厌氧生物Clostridium pasteurianum：巴斯德羧菌属Medical microbiology and immunology：医学微生物学和免疫学Aquatic microbiology：水生微生物学Microbial ecology：微生物生态学Microbial systematic：微生物的系统学Microbial physiology：微生物生理学Cytology ：细胞学Bacterial genetics：细菌遗传学Chapter 2Evolutionary History：进化史Elements：原理，基础Viral Structure：病毒结构The Tree of Life：生命树Physiological：生理学的Eukaryotic：真核的Cytoplasmic (cell)membrane：细胞质膜Cytoplasm：细胞质Macromolecules：大分子Ribosome：核糖体organic molecules：有机分子inorganic ions：无机离子rod-shaped prokaryote：杆状原核生物organelles：细胞器Archaea：古生菌Nucleus：细胞核（nuclear的复数）Mitochondrion （Mitochondrion复数）线粒体Chloroplast：叶绿体Metazoans：后生生物Cytoplasmic：细胞质的Membrane：膜，隔膜Endoplasmic reticulum：内质网Nucleoid：类核，拟核Nucleolus：核仁Nuclear：核的，细胞核Static：静态的metabolic abilities：代谢能力biosynthetic：生物合成genetic alterations：遗传改造Genomes：基因组Chromosome：染色体Circular：环状copy：拷贝haploid：单倍体extrachromosomal：染色体外的。
微生物文献翻译
微生物文献翻译张宇生物科学2011031021Ethanol, isopropanol, and 1-butanol are the only naturally produced alcohol biofuels. Isopropanol can be used directly as a fuel supplement to gasoline or as a feedstock for the transesterification of fats into biodiesel [35]. Both isopropanol and 1-butanol are produced in a mixed product fermentation in various strains of Clostridium [36], with maximum production levels reaching 2 g/L and 20 g/L, respectively [37, 38]. With a renewed interest in alternative fuels, the production of isopropanol and 1-butanol has been recently investigated in genetically tractable heterologous organisms. These organisms, such as Escherichia coli and Saccharomyces cerevisiae, facilitate the design and optimization of new biofuels processes by combining an increasing synthetic biology toolbox with a well-studied metabolism. Isopropanol production in E. coli has surpassed that of Clostridium by assembling the pathway for acetone production and a secondary alcohol dehydrogenase [8, 12]. The production of 1-butanol, however, has proven to be more difficult. Initial efforts were able to produce ~0.5 g/L using E. coli as a host [7]. Construction of a new strain harboring a single construct resulted in an increase in production to 1.2 g/L [9]. In addition to E. coli, 1-butanol production has been investigated in Pseudomonas putida, Bacillus subtilis, and S. cerevisiae [10, 11], although production in E. coli has thus far shown the most promise. Each ofthese processes, however, is far from industrial feasibility, as yields (~0.05 g/g) and productivities (~0.01 g/L/h) must increase significantly to match the same figures for corn ethanol (~0.5 g/g and 2 g/L/h). The advancement of these processes is thought to be limited by the low activity of pathway enzymes due to poor expression, solubility, or oxygen sensitivity, as well as the metabolic imbalance introduced by these heterologous pathways. While productivity in each of these platforms is low in comparison with Clostridial fermentation, the ability to engineer and manipulate these user-friendly hosts will facilitate the development of these processes.翻译：唯一的自然生产的酒精燃料乙醇、异丙醇、和1-丁醇。
有关微生物的英语作文
有关微生物的英语作文Microorganisms, also known as microbes, are tiny living organisms that cannot be seen with the naked eye. Theyexist everywhere, from the air we breathe to the soil we walk on. They play a vital role in our lives and the environment, although their significance is often overlooked. In this essay, I will discuss the importance of microorganisms and their impact on various aspects of our lives.Microorganisms are incredibly diverse and can be found in various forms such as bacteria, viruses, fungi, and protozoa. They have adapted to survive in extreme conditions, including hot springs, deep-sea vents, and even inside the human body. These organisms have the ability to reproduce rapidly, allowing them to quickly adapt to changes in their environment.One of the most significant contributions of microorganisms is their role in nutrient cycling. Theybreak down organic matter, such as dead plants and animals, and release essential nutrients back into the environment. This process, known as decomposition, is crucial for maintaining the balance of ecosystems. Without microorganisms, the Earth would be filled with decaying matter and nutrients would not be recycled efficiently.Microorganisms are also involved in the production of various foods and beverages. For example, yeast, a type of fungus, is used in the fermentation process to produce bread, beer, and wine. Bacteria, such as Lactobacillus, are used in the production of yogurt and cheese. These microorganisms convert sugars into acids, alcohol, and other compounds, giving these products their distinct flavors and textures.Furthermore, microorganisms play a vital role in medicine. Antibiotics, which are used to treat bacterial infections, are derived from microorganisms. For instance, penicillin, one of the first antibiotics discovered, is produced by a type of mold called Penicillium. In addition, microorganisms are used in the production of vaccines,insulin, and other pharmaceutical products. They are also being studied for their potential in cancer treatment and the development of new drugs.Microorganisms are not only beneficial but can also cause harm. Pathogenic microorganisms, such as certain bacteria and viruses, can cause infectious diseases in humans, animals, and plants. These diseases can range from mild to severe and can have a significant impact on public health. It is essential to understand and study these microorganisms to develop effective strategies for prevention and treatment.In conclusion, microorganisms are essential for our survival and the health of the planet. They play a crucial role in nutrient cycling, food production, medicine, and the balance of ecosystems. However, they can also pose a threat to our health. Therefore, it is important to continue studying and understanding microorganisms to harness their benefits while minimizing their negative impacts.【中文回答】。
微生物发酵中英文对照外文翻译文献
中英文对照外文翻译文献葡萄栽培过程中产生废弃物的侧耳属菇类生物降解：一种微生物和人类食物的来源及其在动物养殖中的潜在用途在通过侧耳属菌（平菇）程序进行葡萄园剪枝和葡萄皮渣的生物转化过程中，使用固态发酵技术受到了高度评价。
我们对水果实体的生产和收获之后被酶作用物的化学变化进行了测量计算，发现生物学效率和生物转化率各自都发生了变化，分别从37.2% 上升至78.7%和16.7%上升至 38.8%。
对于菌丝生长和蘑菇产量提高最有益的基质是与葡萄园剪枝项目相混合操作。
葡萄园修剪产生的枝条与葡萄皮渣相比具有较高的酚类成分、总糖、更好的c/n比值、天然脂肪和总氨。
与之相反，在纯葡萄皮渣的实验中，菌丝生长得非常缓慢甚至是不会生长。
葡萄皮渣比例较高的混合物中水分、蛋白质、脂肪和木质素含量一般较高，然而修剪产生的葡萄枝中，中性洗涤剂纤维、半纤维素、纤维素含量较高。
侧耳菌株的生长可能依赖于基质中纤维成分的可获取情况，而且其消化过程中发生的动态变化可能随着这些纤维在真菌生长过程中的改变而发生。
通过以侧耳属菌为媒介的SSF技术对葡萄栽培残基进行回收利用的潜力巨大，可以生产出人类所需的食物以及在反刍动物饲养中还有限使用的高纤维饲料。
关键词：生物转化酶作用；侧耳属菌；回收利用；固态发酵；葡萄栽培过程的副产品引言：葡萄种植是墨西哥西北部一项重要的生产活动，在墨西哥西北部有33500公顷的土地栽培了数类不同品种的葡萄。
这么大规模的生产活动每年大约产生了大约27万吨的工农业废料，而这其中有大约93%是葡萄园修剪掉的枝条。
这些废料一般直接在田间进行焚烧处理，以防止种植物病原菌的扩散，从而引起环境和生态问题以及危害人类健康的风险。
木质素是工农业废料中所有碳含量的主要组成部分，当它在遇热降解过程中会产生多环芳香烃成分，如苯并芘、邻苯二酚、对苯二酚菲和萘。
所有这些化合物可以抑制DNA 合成，并可能诱发动物和人类的肝脏、肺、喉和子宫颈产生癌变肿瘤。
益生菌肠道微生物的基因组学英文论文及翻译
The genomics of probiotic intestinal microorganismsSeppo Salminen1 , Jussi Nurmi2 and Miguel Gueimonde1(1) Functional Foods Forum, University of Turku, FIN-20014 Turku, Finland(2) Department of Biotechnology, University of Turku, FIN-20014 Turku, FinlandSeppo SalminenEmail: *********************Published online: 29 June 2005AbstractAn intestinal population of beneficial commensal microorganisms helps maintain human health, and some of these bacteria have been found to significantly reduce the risk of gut-associated disease and to alleviate disease symptoms. The genomic characterization of probiotic bacteria and other commensal intestinal bacteria that is now under way will help to deepen our understanding of their beneficial effects.While the sequencing of the human genome [1, 2] has increased ourunderstanding of the role of genetic factors in health and disease, each human being harbors many more genes than those in their own genome. These belong to our commensal and symbiotic intestinal microorganisms - our intestinal 'microbiome' - which play an important role in maintaining human health and well-being. A more appropriate image of ourselves would be drawn if the genomes of our intestinal microbiota were taken into account. The microbiome may contain more than 100 times the number of genes in the human genome [3] and provides many functions that humans have thus not needed to develop themselves. The indigenous intestinal microbiota provides a barrier against pathogenic bacteria and other harmful food components [4–6]. It has also been shown to have a direct impact on the morphology of the gut [7], and many intestinal diseases can be linked to disturbances in the intestinal microbial population [8].The indigenous microbiota of an infant's gastrointestinal tract is originally created through contact with the diverse microbiota of the parents and the immediate environment. During breast feeding, initial microbial colonization is enhanced by galacto-oligosaccharides in breast milk and contact with the skin microbiota of the mother. This early colonization process directs the microbial succession until weaning and forms the basis for a healthy microbiota. The viable microbes in the adultintestine outnumber the cells in the human body tenfold, and the composition of this microbial population throughout life is unique to each human being. During adulthood and aging the composition and diversity of the microbiota can vary as a result of disease and the genetic background of the individual.Current research into the intestinal microbiome is focused on obtaining genomic data from important intestinal commensals and from probiotics, microorganisms that appear to actively promote health. This genomic information indicates that gut commensals not only derive food and other growth factors from the intestinal contents but also influence their human hosts by providing maturational signals for the developing infant and child, as well as providing signals that can lead to an alteration in the barrier mechanisms of the gut. It has been reported that colonization by particular bacteria has a major role in rapidly providing humans with energy from their food [9]. For example, the intestinal commensal Bacteroides thetaiotaomicron has been shown to have a major role in this process, and whole-genome transcriptional profiling of the bacterium has shown that specific diets can be associated with selective upregulation of bacterial genes that facilitate delivery of products of carbohydrate breakdown to the host's energy metabolism [10, 11]. Key microbial groups in the intestinal microbiota are highly flexible in adapting to changes in diet, and thus detailed prediction of their actions and effects may be difficult. Although genomic studies have revealed important details about the impact of the intestinal microbiota on specific processes [3, 11–14], the effects of species composition and microbial diversity and their potential compensatory functions are still not understood.Probiotics and healthA probiotic has been defined by a working group of the International Life Sciences Institute Europe (ILSI Europe) as "a viable microbial food supplement which beneficially influences the health of the host" [15]. Probiotics are usually members of the healthy gut microbiota and their addition can assist in returning a disturbed microbiota to its normal beneficial composition. The ILSI definition implies that safety and efficacy must be scientifically demonstrated for each new probiotic strain and product. Criteria for selecting probiotics that are specific for a desired target have been developed, but general criteria that must be satisfied include the ability to adhere to intestinal mucosa and tolerance of acid and bile. Such criteria have proved useful but cumbersome in current selection processes, as there are several adherence mechanisms and they influence gene upregulation differently in the host. Therefore, two different adhesion studies need to be conducted on each strain and theirpredictive value for specific functions is not always good or optimal. Demonstration of the effects of probiotics on health includes research on mechanisms and clinical intervention studies with human subjects belonging to target groups.The revelation of the human genome sequence has increased our understanding of the genetic deviations that lead to or predispose to gastrointestinal disease as well as to diseases associated with the gut, such as food allergies. In 1995, the first genome of a free-living organism, the bacterium Haemophilus influenzae, was sequenced [16]. Since then, over 200 bacterial genome sequences, mainly of pathogenic microorganisms, have been completed. The first genome of a mammalian lactic-acid bacterium, that of Lactococcus lactis, a microorganism of great industrial interest, was completed in 2001 [17]. More recently, the genomes of numerous other lactic-acid bacteria [18], bifidobacteria [12] and other intestinal microorganisms [13, 19, 20] have been sequenced, and others are under way [21]. Table 1lists the probiotic bacteria that have been sequenced. These great breakthroughs have demonstrated that evolution has adapted both microbes and humans to their current state of cohabitation, or even symbiosis, which is beneficial to both parties and facilitates a healthy and relatively stable but adaptable gut environment.Table 1Lessons from genomesLactic-acid bacteria and bifidobacteria can act as biomarkers of gut health by giving early warning of aberrations that represent a risk of specific gut diseases. Only a few members of the genera Lactobacillus and Bifidobacterium, two genera that provide many probiotics, have been completely sequenced. The key issue for the microbiota, for probiotics, and for their human hosts is the flexibility of the microorganisms in coping with a changeable local environment and microenvironments.This flexibility is emphasized in the completed genomes of intestinal and probiotic microorganisms. The complete genome sequence of the probiotic Lactobacillus acidophilus NCFM has recently been published by Altermann et al. [22]. The genome is relatively small and the bacterium appears to be unable to synthesize several amino acids, vitamins and cofactors. Italso encodes a number of permeases, glycolases and peptidases for rapid uptake and utilization of sugars and amino acids from the human intestine, especially the upper gastrointestinal tract. The authors also report a number of cell-surface proteins, such as mucus- and fibronectin-binding proteins, that enable this strain to adhere to the intestinal epithelium and to exchange signals with the intestinal immune system. Flexibility is guaranteed by a number of regulatory systems, including several transcriptional regulators, six PurR-type repressors and ninetwo-component systems, and by a variety of sugar transporters. The genome of another probiotic, Lactobacillus johnsonii [23], also lacks some genes involved in the synthesis of amino acids, purine nucleotides and numerous cofactors, but contains numerous peptidases, amino-acid permeases and other transporters, indicating a strong dependence on the host.The presence of bile-salt hydrolases and transporters in these bacteria indicates an adaptation to the upper gastrointestinal tract [23], enabling the bacteria to survive the acidic and bile-rich environments of the stomach and small intestine. In this regard, bile-salt hydrolases have been found in most of the sequenced genomes of bifidobacteria and lactic-acid bacteria [24], and these enzymes can have a significant impact on bacterial survival. Another lactic-acid bacterium, Lactobacillus plantarum WCFS1, also contains a large number of genes related to carbohydrate transport and utilization, and has genes for the production of exopolysaccharides and antimicrobial agents [18], indicating a good adaptation to a variety of environments, including the human small intestine [14]. In general, flexibility and adaptability are reflected by a large number of regulatory and transport functions.Microorganisms that inhabit the human colon, such as B. thetaiotaomicron and Bifidobacterium longum [12], have a great number of genes devoted to oligosaccharide transport and metabolism, indicating adaptation to life in the large intestine and differentiating them from, for example, L. johnsonii [23]. Genomic research has also provided initial information on the relationship between components of the diet and intestinal microorganisms. The genome of B. longum [12] suggests the ability to scan for nutrient availability in the lower gastrointestinal tract in human infants. This strain is adapted to utilizing the oligosaccharides in human milk along with intestinal mucins that are available in the colon of breast-fed infants. On the other hand, the genome of L. acidophilus has a gene cluster related to the metabolism of fructo-oligosaccharides, carbohydrates that are commonly used as prebiotics, or substrates to肠道微生物益生菌的基因组学塞波萨米宁，尤西鲁米和米格尔哥尔摩得（1）功能性食品论坛，图尔库大学，FIN-20014芬兰图尔库（2）土尔库大学生物技术系，FIN-20014芬兰图尔库塞波萨米宁电子邮件：seppo.salminen utu.fi线上发表于2005年6月29日摘要肠道有益的共生微生物有助于维护人体健康，一些这些细菌被发现显着降低肠道疾病的风险和减轻疾病的症状。
关于微生物的英文作文
关于微生物的英文作文English: Microorganisms, also known as microbes, are tiny organisms that can only be seen under a microscope. They are highly diverse and can be found in almost every environment on Earth, from the depths of the ocean to the soil beneath our feet. Microorganisms play crucial roles in various ecological processes, such as nutrient cycling and decomposition. They also have significant impacts on human health, both positive and negative. For example, some microbes are used in the production of food and medicine, while others can cause diseases and infections. Understanding the behavior and function of microorganisms is essential for various fields, including biology, medicine, and environmental science.中文翻译: 微生物，也称为微生物，在显微镜下才能看到的微小生物体。
它们具有极高的多样性，并且几乎可以在地球上的每个环境中找到，从深海到我们脚下的土壤。
微生物在各种生态过程中扮演着关键的角色，如营养循环和分解作用。
微生物英文文献及翻译—原文
Dynamic and distribution of ammonia-oxidizing bacteria communities during sludge granulation in an anaerobic e aerobic sequencing batch reactorZhang Bin a ,b ,Chen Zhe a ,b ,Qiu Zhigang a ,b ,Jin Min a ,b ,Chen Zhiqiang a ,b ,Chen Zhaoli a ,b ,Li Junwen a ,b ,Wang Xuan c ,*,Wang Jingfeng a ,b ,**aInstitute of Hygiene and Environmental Medicine,Academy of Military Medical Sciences,Tianjin 300050,PR China bTianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety,Tianjin 300050,PR China cTianjin Key Laboratory of Hollow Fiber Membrane Material and Membrane Process,Institute of Biological and Chemical Engineering,Tianjin Polytechnical University,Tianjin 300160,PR Chinaa r t i c l e i n f oArticle history:Received 30June 2011Received in revised form 10September 2011Accepted 10September 2011Available online xxx Keywords:Ammonia-oxidizing bacteria Granular sludgeCommunity development Granule sizeNitrifying bacteria distribution Phylogenetic diversitya b s t r a c tThe structure dynamic of ammonia-oxidizing bacteria (AOB)community and the distribution of AOB and nitrite-oxidizing bacteria (NOB)in granular sludge from an anaerobic e aerobic sequencing batch reactor (SBR)were investigated.A combination of process studies,molecular biotechniques and microscale techniques were employed to identify and characterize these organisms.The AOB community structure in granules was substantially different from that of the initial pattern of the inoculants sludge.Along with granules formation,the AOB diversity declined due to the selection pressure imposed by process conditions.Denaturing gradient gel electrophoresis (DGGE)and sequencing results demonstrated that most of Nitrosomonas in the inoculating sludge were remained because of their ability to rapidly adapt to the settling e washing out action.Furthermore,DGGE analysis revealed that larger granules benefit more AOB species surviving in the reactor.In the SBR were various size granules coexisted,granule diameter affected the distribution range of AOB and NOB.Small and medium granules (d <0.6mm)cannot restrict oxygen mass transfer in all spaces of the rger granules (d >0.9mm)can result in smaller aerobic volume fraction and inhibition of NOB growth.All these observations provide support to future studies on the mechanisms responsible for the AOB in granules systems.ª2011Elsevier Ltd.All rights reserved.1.IntroductionAt sufficiently high levels,ammonia in aquatic environments can be toxic to aquatic life and can contribute to eutrophica-tion.Accordingly,biodegradation and elimination of ammonia in wastewater are the primary functions of thewastewater treatment process.Nitrification,the conversion of ammonia to nitrate via nitrite,is an important way to remove ammonia nitrogen.It is a two-step process catalyzed by ammonia-oxidizing and nitrite-oxidizing bacteria (AOB and NOB).Aerobic ammonia-oxidation is often the first,rate-limiting step of nitrification;however,it is essential for the*Corresponding author .**Corresponding author.Institute of Hygiene and Environmental Medicine,Academy of Military Medical Sciences,Tianjin 300050,PR China.Tel.:+862284655498;fax:+862223328809.E-mail addresses:wangxuan0116@ (W.Xuan),jingfengwang@ (W.Jingfeng).Available online atjournal homepage:/locate/watresw a t e r r e s e a r c h x x x (2011)1e 100043-1354/$e see front matter ª2011Elsevier Ltd.All rights reserved.doi:10.1016/j.watres.2011.09.026removal of ammonia from the wastewater(Prosser and Nicol, 2008).Comparative analyses of16S rRNA sequences have revealed that most AOB in activated sludge are phylogeneti-cally closely related to the clade of b-Proteobacteria (Kowalchuk and Stephen,2001).However,a number of studies have suggested that there are physiological and ecological differences between different AOB genera and lineages,and that environmental factors such as process parameter,dis-solved oxygen,salinity,pH,and concentrations of free ammonia can impact certain species of AOB(Erguder et al., 2008;Kim et al.,2006;Koops and Pommerening-Ro¨ser,2001; Kowalchuk and Stephen,2001;Shi et al.,2010).Therefore, the physiological activity and abundance of AOB in waste-water processing is critical in the design and operation of waste treatment systems.For this reason,a better under-standing of the ecology and microbiology of AOB in waste-water treatment systems is necessary to enhance treatment performance.Recently,several developed techniques have served as valuable tools for the characterization of microbial diversity in biological wastewater treatment systems(Li et al., 2008;Yin and Xu,2009).Currently,the application of molec-ular biotechniques can provide clarification of the ammonia-oxidizing community in detail(Haseborg et al.,2010;Tawan et al.,2005;Vlaeminck et al.,2010).In recent years,the aerobic granular sludge process has become an attractive alternative to conventional processes for wastewater treatment mainly due to its cell immobilization strategy(de Bruin et al.,2004;Liu et al.,2009;Schwarzenbeck et al.,2005;Schwarzenbeck et al.,2004a,b;Xavier et al.,2007). Granules have a more tightly compact structure(Li et al.,2008; Liu and Tay,2008;Wang et al.,2004)and rapid settling velocity (Kong et al.,2009;Lemaire et al.,2008).Therefore,granular sludge systems have a higher mixed liquid suspended sludge (MLSS)concentration and longer solid retention times(SRT) than conventional activated sludge systems.Longer SRT can provide enough time for the growth of organisms that require a long generation time(e.g.,AOB).Some studies have indicated that nitrifying granules can be cultivated with ammonia-rich inorganic wastewater and the diameter of granules was small (Shi et al.,2010;Tsuneda et al.,2003).Other researchers reported that larger granules have been developed with the synthetic organic wastewater in sequencing batch reactors(SBRs)(Li et al., 2008;Liu and Tay,2008).The diverse populations of microor-ganisms that coexist in granules remove the chemical oxygen demand(COD),nitrogen and phosphate(de Kreuk et al.,2005). However,for larger granules with a particle diameter greater than0.6mm,an outer aerobic shell and an inner anaerobic zone coexist because of restricted oxygen diffusion to the granule core.These properties of granular sludge suggest that the inner environment of granules is unfavorable to AOB growth.Some research has shown that particle size and density induced the different distribution and dominance of AOB,NOB and anam-mox(Winkler et al.,2011b).Although a number of studies have been conducted to assess the ecology and microbiology of AOB in wastewater treatment systems,the information on the dynamics,distribution,and quantification of AOB communities during sludge granulation is still limited up to now.To address these concerns,the main objective of the present work was to investigate the population dynamics of AOB communities during the development of seedingflocs into granules,and the distribution of AOB and NOB in different size granules from an anaerobic e aerobic SBR.A combination of process studies,molecular biotechniques and microscale techniques were employed to identify and char-acterize these organisms.Based on these approaches,we demonstrate the differences in both AOB community evolu-tion and composition of theflocs and granules co-existing in the SBR and further elucidate the relationship between distribution of nitrifying bacteria and granule size.It is ex-pected that the work would be useful to better understand the mechanisms responsible for the AOB in granules and apply them for optimal control and management strategies of granulation systems.2.Material and methods2.1.Reactor set-up and operationThe granules were cultivated in a lab-scale SBR with an effective volume of4L.The effective diameter and height of the reactor was10cm and51cm,respectively.The hydraulic retention time was set at8h.Activated sludge from a full-scale sewage treat-ment plant(Jizhuangzi Sewage Treatment Works,Tianjin, China)was used as the seed sludge for the reactor at an initial sludge concentration of3876mg LÀ1in MLSS.The reactor was operated on6-h cycles,consisting of2-min influent feeding,90-min anaerobic phase(mixing),240-min aeration phase and5-min effluent discharge periods.The sludge settling time was reduced gradually from10to5min after80SBR cycles in20days, and only particles with a settling velocity higher than4.5m hÀ1 were retained in the reactor.The composition of the influent media were NaAc(450mg LÀ1),NH4Cl(100mg LÀ1),(NH4)2SO4 (10mg LÀ1),KH2PO4(20mg LÀ1),MgSO4$7H2O(50mg LÀ1),KCl (20mg LÀ1),CaCl2(20mg LÀ1),FeSO4$7H2O(1mg LÀ1),pH7.0e7.5, and0.1mL LÀ1trace element solution(Li et al.,2007).Analytical methods-The total organic carbon(TOC),NHþ4e N, NOÀ2e N,NOÀ3e N,total nitrogen(TN),total phosphate(TP) concentration,mixed liquid suspended solids(MLSS) concentration,and sludge volume index at10min(SVI10)were measured regularly according to the standard methods (APHA-AWWA-WEF,2005).Sludge size distribution was determined by the sieving method(Laguna et al.,1999).Screening was performed with four stainless steel sieves of5cm diameter having respective mesh openings of0.9,0.6,0.45,and0.2mm.A100mL volume of sludge from the reactor was sampled with a calibrated cylinder and then deposited on the0.9mm mesh sieve.The sample was subsequently washed with distilled water and particles less than0.9mm in diameter passed through this sieve to the sieves with smaller openings.The washing procedure was repeated several times to separate the gran-ules.The granules collected on the different screens were recovered by backwashing with distilled water.Each fraction was collected in a different beaker andfiltered on quantitative filter paper to determine the total suspended solid(TSS).Once the amount of total suspended solid(TSS)retained on each sieve was acquired,it was reasonable to determine for each class of size(<0.2,[0.2e0.45],[0.45e0.6],[0.6e0.9],>0.9mm) the percentage of the total weight that they represent.w a t e r r e s e a r c h x x x(2011)1e10 22.2.DNA extraction and nested PCR e DGGEThe sludge from approximately8mg of MLSS was transferred into a1.5-mL Eppendorf tube and then centrifuged at14,000g for10min.The supernatant was removed,and the pellet was added to1mL of sodium phosphate buffer solution and aseptically mixed with a sterilized pestle in order to detach granules.Genomic DNA was extracted from the pellets using E.Z.N.A.äSoil DNA kit(D5625-01,Omega Bio-tek Inc.,USA).To amplify ammonia-oxidizer specific16S rRNA for dena-turing gradient gel electrophoresis(DGGE),a nested PCR approach was performed as described previously(Zhang et al., 2010).30m l of nested PCR amplicons(with5m l6Âloading buffer)were loaded and separated by DGGE on polyacrylamide gels(8%,37.5:1acrylamide e bisacrylamide)with a linear gradient of35%e55%denaturant(100%denaturant¼7M urea plus40%formamide).The gel was run for6.5h at140V in 1ÂTAE buffer(40mM Tris-acetate,20mM sodium acetate, 1mM Na2EDTA,pH7.4)maintained at60 C(DCodeäUniversal Mutation Detection System,Bio-Rad,Hercules,CA, USA).After electrophoresis,silver-staining and development of the gels were performed as described by Sanguinetti et al. (1994).These were followed by air-drying and scanning with a gel imaging analysis system(Image Quant350,GE Inc.,USA). The gel images were analyzed with the software Quantity One,version4.31(Bio-rad).Dice index(Cs)of pair wise community similarity was calculated to evaluate the similarity of the AOB community among DGGE lanes(LaPara et al.,2002).This index ranges from0%(no common band)to100%(identical band patterns) with the assistance of Quantity One.The Shannon diversity index(H)was used to measure the microbial diversity that takes into account the richness and proportion of each species in a population.H was calculatedusing the following equation:H¼ÀPn iNlogn iN,where n i/Nis the proportion of community made up by species i(bright-ness of the band i/total brightness of all bands in the lane).Dendrograms relating band pattern similarities were automatically calculated without band weighting(consider-ation of band density)by the unweighted pair group method with arithmetic mean(UPGMA)algorithms in the Quantity One software.Prominent DGGE bands were excised and dissolved in30m L Milli-Q water overnight,at4 C.DNA was recovered from the gel by freeze e thawing thrice.Cloning and sequencing of the target DNA fragments were conducted following the estab-lished method(Zhang et al.,2010).2.3.Distribution of nitrifying bacteriaThree classes of size([0.2e0.45],[0.45e0.6],>0.9mm)were chosen on day180for FISH analysis in order to investigate the spatial distribution characteristics of AOB and NOB in granules.2mg sludge samples werefixed in4%para-formaldehyde solution for16e24h at4 C and then washed twice with sodium phosphate buffer;the samples were dehydrated in50%,80%and100%ethanol for10min each. Ethanol in the granules was then completely replaced by xylene by serial immersion in ethanol-xylene solutions of3:1, 1:1,and1:3by volume andfinally in100%xylene,for10min periods at room temperature.Subsequently,the granules were embedded in paraffin(m.p.56e58 C)by serial immer-sion in1:1xylene-paraffin for30min at60 C,followed by 100%paraffin.After solidification in paraffin,8-m m-thick sections were prepared and placed on gelatin-coated micro-scopic slides.Paraffin was removed by immersing the slide in xylene and ethanol for30min each,followed by air-drying of the slides.The three oligonucleotide probes were used for hybridiza-tion(Downing and Nerenberg,2008):FITC-labeled Nso190, which targets the majority of AOB;TRITC-labeled NIT3,which targets Nitrobacter sp.;TRITC-labeled NSR1156,which targets Nitrospira sp.All probe sequences,their hybridization condi-tions,and washing conditions are given in Table1.Oligonu-cleotides were synthesized andfluorescently labeled with fluorochomes by Takara,Inc.(Dalian,China).Hybridizations were performed at46 C for2h with a hybridization buffer(0.9M NaCl,formamide at the percentage shown in Table1,20mM Tris/HCl,pH8.0,0.01% SDS)containing each labeled probe(5ng m LÀ1).After hybrid-ization,unbound oligonucleotides were removed by a strin-gent washing step at48 C for15min in washing buffer containing the same components as the hybridization buffer except for the probes.For detection of all DNA,4,6-diamidino-2-phenylindole (DAPI)was diluted with methanol to afinal concentration of1ng m LÀ1.Cover the slides with DAPI e methanol and incubate for15min at37 C.The slides were subsequently washed once with methanol,rinsed briefly with ddH2O and immediately air-dried.Vectashield(Vector Laboratories)was used to prevent photo bleaching.The hybridization images were captured using a confocal laser scanning microscope (CLSM,Zeiss710).A total of10images were captured for each probe at each class of size.The representative images were selected andfinal image evaluation was done in Adobe PhotoShop.w a t e r r e s e a r c h x x x(2011)1e1033.Results3.1.SBR performance and granule characteristicsDuring the startup period,the reactor removed TOC and NH 4þ-N efficiently.98%of NH 4þ-N and 100%of TOC were removed from the influent by day 3and day 5respectively (Figs.S2,S3,Supporting information ).Removal of TN and TP were lower during this period (Figs.S3,S4,Supporting information ),though the removal of TP gradually improved to 100%removal by day 33(Fig.S4,Supporting information ).To determine the sludge volume index of granular sludge,a settling time of 10min was chosen instead of 30min,because granular sludge has a similar SVI after 60min and after 5min of settling (Schwarzenbeck et al.,2004b ).The SVI 10of the inoculating sludge was 108.2mL g À1.The changing patterns of MLSS and SVI 10in the continuous operation of the SBR are illustrated in Fig.1.The sludge settleability increased markedly during the set-up period.Fig.2reflects the slow andgradual process of sludge granulation,i.e.,from flocculentsludge to granules.3.2.DGGE analysis:AOB communities structure changes during sludge granulationThe results of nested PCR were shown in Fig.S1.The well-resolved DGGE bands were obtained at the representative points throughout the GSBR operation and the patterns revealed that the structure of the AOB communities was dynamic during sludge granulation and stabilization (Fig.3).The community structure at the end of experiment was different from that of the initial pattern of the seed sludge.The AOB communities on day 1showed 40%similarity only to that at the end of the GSBR operation (Table S1,Supporting information ),indicating the considerable difference of AOB communities structures between inoculated sludge and granular sludge.Biodiversity based on the DGGE patterns was analyzed by calculating the Shannon diversity index H as204060801001201401254159738494104115125135147160172188Time (d)S V I 10 (m L .g -1)10002000300040005000600070008000900010000M L S S (m g .L -1)Fig.1e Change in biomass content and SVI 10during whole operation.SVI,sludge volume index;MLSS,mixed liquid suspendedsolids.Fig.2e Variation in granule size distribution in the sludge during operation.d,particle diameter;TSS,total suspended solids.w a t e r r e s e a r c h x x x (2011)1e 104shown in Fig.S5.In the phase of sludge inoculation (before day 38),H decreased remarkably (from 0.94to 0.75)due to the absence of some species in the reactor.Though several dominant species (bands2,7,10,11)in the inoculating sludge were preserved,many bands disappeared or weakened (bands 3,4,6,8,13,14,15).After day 45,the diversity index tended to be stable and showed small fluctuation (from 0.72to 0.82).Banding pattern similarity was analyzed by applying UPGMA (Fig.4)algorithms.The UPGMA analysis showed three groups with intragroup similarity at approximately 67%e 78%and intergroup similarity at 44e 62%.Generally,the clustering followed the time course;and the algorithms showed a closer clustering of groups II and III.In the analysis,group I was associated with sludge inoculation and washout,group IIwithFig.3e DGGE profile of the AOB communities in the SBR during the sludge granulation process (lane labels along the top show the sampling time (days)from startup of the bioreactor).The major bands were labeled with the numbers (bands 1e15).Fig.4e UPGMA analysis dendrograms of AOB community DGGE banding patterns,showing schematics of banding patterns.Roman numerals indicate major clusters.w a t e r r e s e a r c h x x x (2011)1e 105startup sludge granulation and decreasing SVI 10,and group III with a stable system and excellent biomass settleability.In Fig.3,the locations of the predominant bands were excised from the gel.DNA in these bands were reamplified,cloned and sequenced.The comparative analysis of these partial 16S rRNA sequences (Table 2and Fig.S6)revealed the phylogenetic affiliation of 13sequences retrieved.The majority of the bacteria in seed sludge grouped with members of Nitrosomonas and Nitrosospira .Along with sludge granula-tion,most of Nitrosomonas (Bands 2,5,7,9,10,11)were remained or eventually became dominant in GSBR;however,all of Nitrosospira (Bands 6,13,15)were gradually eliminated from the reactor.3.3.Distribution of AOB and NOB in different sized granulesFISH was performed on the granule sections mainly to deter-mine the location of AOB and NOB within the different size classes of granules,and the images were not further analyzed for quantification of cell counts.As shown in Fig.6,in small granules (0.2mm <d <0.45mm),AOB located mainly in the outer part of granular space,whereas NOB were detected only in the core of granules.In medium granules (0.45mm <d <0.6mm),AOB distributed evenly throughout the whole granular space,whereas NOB still existed in the inner part.In the larger granules (d >0.9mm),AOB and NOB were mostly located in the surface area of the granules,and moreover,NOB became rare.4.Discussion4.1.Relationship between granule formation and reactor performanceAfter day 32,the SVI 10stabilized at 20e 35mL g À1,which is very low compared to the values measured for activated sludge (100e 150mL g À1).However,the size distribution of the granules measured on day 32(Fig.2)indicated that only 22%of the biomass was made of granular sludge with diameter largerthan 0.2mm.These results suggest that sludge settleability increased prior to granule formation and was not affected by different particle sizes in the sludge during the GSBR operation.It was observed,however,that the diameter of the granules fluctuated over longer durations.The large granules tended to destabilize due to endogenous respiration,and broke into smaller granules that could seed the formation of large granules again.Pochana and Keller reported that physically broken sludge flocs contribute to lower denitrification rates,due to their reduced anoxic zone (Pochana and Keller,1999).Therefore,TN removal efficiency raises fluctuantly throughout the experiment.Some previous research had demonstrated that bigger,more dense granules favored the enrichment of PAO (Winkler et al.,2011a ).Hence,after day 77,removal efficiency of TP was higher and relatively stable because the granules mass fraction was over 90%and more larger granules formed.4.2.Relationship between AOB communities dynamic and sludge granulationFor granule formation,a short settling time was set,and only particles with a settling velocity higher than 4.5m h À1were retained in the reactor.Moreover,as shown in Fig.1,the variation in SVI 10was greater before day 41(from 108.2mL g À1e 34.1mL g À1).During this phase,large amounts of biomass could not survive in the reactor.A clear shift in pop-ulations was evident,with 58%similarity between days 8and 18(Table S1).In the SBR system fed with acetate-based synthetic wastewater,heterotrophic bacteria can produce much larger amounts of extracellular polysaccharides than autotrophic bacteria (Tsuneda et al.,2003).Some researchers found that microorganisms in high shear environments adhered by extracellular polymeric substances (EPS)to resist the damage of suspended cells by environmental forces (Trinet et al.,1991).Additionally,it had been proved that the dominant heterotrophic species in the inoculating sludge were preserved throughout the process in our previous research (Zhang et al.,2011).It is well known that AOB are chemoau-totrophic and slow-growing;accordingly,numerous AOBw a t e r r e s e a r c h x x x (2011)1e 106populations that cannot become big and dense enough to settle fast were washed out from the system.As a result,the variation in AOB was remarkable in the period of sludge inoculation,and the diversity index of population decreased rapidly.After day 45,AOB communities’structure became stable due to the improvement of sludge settleability and the retention of more biomass.These results suggest that the short settling time (selection pressure)apparently stressed the biomass,leading to a violent dynamic of AOB communities.Further,these results suggest that certain populations may have been responsible for the operational success of the GSBR and were able to persist despite the large fluctuations in pop-ulation similarity.This bacterial population instability,coupled with a generally acceptable bioreactor performance,is congruent with the results obtained from a membrane biore-actor (MBR)for graywater treatment (Stamper et al.,2003).Nitrosomonas e like and Nitrosospira e like populations are the dominant AOB populations in wastewater treatment systems (Kowalchuk and Stephen,2001).A few previous studies revealed that the predominant populations in AOB communities are different in various wastewater treatment processes (Tawan et al.,2005;Thomas et al.,2010).Some researchers found that the community was dominated by AOB from the genus Nitrosospira in MBRs (Zhang et al.,2010),whereas Nitrosomonas sp.is the predominant population in biofilter sludge (Yin and Xu,2009).In the currentstudy,Fig.5e DGGE profile of the AOB communities in different size of granules (lane labels along the top show the range of particle diameter (d,mm)).Values along the bottom indicate the Shannon diversity index (H ).Bands labeled with the numbers were consistent with the bands in Fig.3.w a t e r r e s e a r c h x x x (2011)1e 107sequence analysis revealed that selection pressure evidently effect on the survival of Nitrosospira in granular sludge.Almost all of Nitrosospira were washed out initially and had no chance to evolve with the environmental changes.However,some members of Nitrosomonas sp.have been shown to produce more amounts of EPS than Nitrosospira ,especially under limited ammonia conditions (Stehr et al.,1995);and this feature has also been observed for other members of the same lineage.Accordingly,these EPS are helpful to communicate cells with each other and granulate sludge (Adav et al.,2008).Therefore,most of Nitrosomonas could adapt to this challenge (to become big and dense enough to settle fast)and were retained in the reactor.At the end of reactor operation (day 180),granules with different particle size were sieved.The effects of variation in granules size on the composition of the AOBcommunitiesFig.6e Micrographs of FISH performed on three size classes of granule sections.DAPI stain micrographs (A,D,G);AOB appear as green fluorescence (B,E,H),and NOB appear as red fluorescence (C,F,I).Bar [100m m in (A)e (C)and (G)e (I).d,particle diameter.(For interpretation of the references to colour in this figure legend,the reader is referred to the web version of this article.)w a t e r r e s e a r c h x x x (2011)1e 108were investigated.As shown in Fig.5,AOB communities structures in different size of granules were varied.Although several predominant bands(bands2,5,11)were present in all samples,only bands3and6appeared in the granules with diameters larger than0.6mm.Additionally,bands7and10 were intense in the granules larger than0.45mm.According to Table2,it can be clearly indicated that Nitrosospira could be retained merely in the granules larger than0.6mm.Therefore, Nitrosospira was not present at a high level in Fig.3due to the lower proportion of larger granules(d>0.6mm)in TSS along with reactor operation.DGGE analysis also revealed that larger granules had a greater microbial diversity than smaller ones. This result also demonstrates that more organisms can survive in larger granules as a result of more space,which can provide the suitable environment for the growth of microbes(Fig.6).4.3.Effect of variance in particle size on the distribution of AOB and NOB in granulesAlthough an influence of granule size has been observed in experiments and simulations for simultaneous N-and P-removal(de Kreuk et al.,2007),the effect of granule size on the distribution of different biomass species need be revealed further with the assistance of visible experimental results, especially in the same granular sludge reactors.Related studies on the diversity of bacterial communities in granular sludge often focus on the distribution of important functional bacteria populations in single-size granules(Matsumoto et al., 2010).In the present study,different size granules were sieved,and the distribution patterns of AOB and NOB were explored.In the nitrification processes considered,AOB and NOB compete for space and oxygen in the granules(Volcke et al.,2010).Since ammonium oxidizers have a higheroxygen affinity(K AOBO2<K NOBO2)and accumulate more rapidly inthe reactor than nitrite oxidizers(Volcke et al.,2010),NOB are located just below the layer of AOB,where still some oxygen is present and allows ready access to the nitrite produced.In smaller granules,the location boundaries of the both biomass species were distinct due to the limited existence space provided by granules for both microorganism’s growth.AOB exist outside of the granules where oxygen and ammonia are present.Medium granules can provide broader space for microbe multiplying;accordingly,AOB spread out in the whole granules.This result also confirms that oxygen could penetrate deep into the granule’s core without restriction when particle diameter is less than0.6mm.Some mathematic model also supposed that NOBs are favored to grow in smaller granules because of the higher fractional aerobic volume (Volcke et al.,2010).As shown in the results of the batch experiments(Zhang et al.,2011),nitrite accumulation temporarily occurred,accompanied by the more large gran-ules(d>0.9mm)forming.This phenomenon can be attrib-uted to the increased ammonium surface load associated with larger granules and smaller aerobic volume fraction,resulting in outcompetes of NOB.It also suggests that the core areas of large granules(d>0.9mm)could provide anoxic environment for the growth of anaerobic denitrificans(such as Tb.deni-trificans or Tb.thioparus in Fig.S7,Supporting information).As shown in Fig.2and Fig.S3,the removal efficiency of total nitrogen increased with formation of larger granules.5.ConclusionsThe variation in AOB communities’structure was remarkable during sludge inoculation,and the diversity index of pop-ulation decreased rapidly.Most of Nitrosomonas in the inocu-lating sludge were retained because of their capability to rapidly adapt to the settling e washing out action.DGGE anal-ysis also revealed that larger granules had greater AOB diversity than that of smaller ones.Oxygen penetration was not restricted in the granules of less than0.6mm particle diameter.However,the larger granules(d>0.9mm)can result in the smaller aerobic volume fraction and inhibition of NOB growth.Henceforth,further studies on controlling and opti-mizing distribution of granule size could be beneficial to the nitrogen removal and expansive application of granular sludge technology.AcknowledgmentsThis work was supported by grants from the National Natural Science Foundation of China(No.51108456,50908227)and the National High Technology Research and Development Program of China(No.2009AA06Z312).Appendix.Supplementary dataSupplementary data associated with this article can be found in online version at doi:10.1016/j.watres.2011.09.026.r e f e r e n c e sAdav,S.S.,Lee, D.J.,Show,K.Y.,2008.Aerobic granular sludge:recent advances.Biotechnology Advances26,411e423.APHA-AWWA-WEF,2005.Standard Methods for the Examination of Water and Wastewater,first ed.American Public Health Association/American Water Works Association/WaterEnvironment Federation,Washington,DC.de Bruin,L.M.,de Kreuk,M.,van der Roest,H.F.,Uijterlinde,C., van Loosdrecht,M.C.M.,2004.Aerobic granular sludgetechnology:an alternative to activated sludge?Water Science and Technology49,1e7.de Kreuk,M.,Heijnen,J.J.,van Loosdrecht,M.C.M.,2005.Simultaneous COD,nitrogen,and phosphate removal byaerobic granular sludge.Biotechnology and Bioengineering90, 761e769.de Kreuk,M.,Picioreanu,C.,Hosseini,M.,Xavier,J.B.,van Loosdrecht,M.C.M.,2007.Kinetic model of a granular sludge SBR:influences on nutrient removal.Biotechnology andBioengineering97,801e815.Downing,L.S.,Nerenberg,R.,2008.Total nitrogen removal ina hybrid,membrane-aerated activated sludge process.WaterResearch42,3697e3708.Erguder,T.H.,Boon,N.,Vlaeminck,S.E.,Verstraete,W.,2008.Partial nitrification achieved by pulse sulfide doses ina sequential batch reactor.Environmental Science andTechnology42,8715e8720.w a t e r r e s e a r c h x x x(2011)1e109。
医学英语文献3课文翻译
医学文献3课文翻译Unit 1-ATranslation of Text A微生物学简介微生物的研究内容是什么？1 微生物学是研究只有借助显微镜才能看得见的微小生物的科学。
微生物种类繁多，包括细菌、蓝细菌、立克次氏体、衣原体、真菌、用显微镜可见的藻类、原生动物和病毒，如图1-1所示。
微生物(microorganism)与微生物(germ)的意思相同吗？2 微生物(microorganism)是大多数人所知的微生物(germ)的科学名称。
“Microorganism”这个术语是一个中性词，而“germ”一般指的是能够引起疾病的某些微生物。
医学微生物学是与病原微生物有关的微生物学的分支。
普通微生物学则包括全部微生物的系谱。
所有微生物皆可引起传染性的疾病吗?3 绝大多数的微生物都与传染病无关，90%以上的微生物对人类生活质量的改善有帮助。
例如，微生物在自然环境中通过碳、氮、硫、磷和其他元素的再循环帮助维持化学元素的平衡。
另外，微生物构成自然界中许多食物链的基础，而且土壤中的微生物还可帮助分解所有死亡的生物尸体。
任何微生物皆能进行光合作用吗？4 光合作用是从日光获得能量用于合成含碳化合物如糖类（碳水化合物）的化学过程，以化学能的形式储存能量。
我们一般认为光合作用是绿色植物的活动范围，但是某些种类的生物能执行光合作用。
如蓝细菌【以前称为蓝绿藻】就有光合作用的酶系统。
它们通过光合作用过程给环境提供许多氧气。
单细胞的藻也进行光合作用，制造为其他生物提供能源的糖类（碳水化合物）。
因此，微生物对所有生物都是有益的。
人类如何从微生物获益？5 人类可以从微生物的活动中获得实实在在的益处。
例如，许多类型的微生物可居住在身体的不同部位，阻止病原菌的生长，皮肤、小肠和大肠就是这样的区域。
微生物产生许多我们吃的食物，包括发酵的奶制品（发酵的乳酪、酸奶酪和酪乳）和发酵的食品如腌渍品、德国泡菜、面包和酒精饮料等。
在工业生产公司，科学家们培养大量的微生物并且利用它们生产维生素、酶、有机酸和其他基本的生长因子。
微生物外文翻译之三
Microbial degradation of PAHs and other hydrophobic substrates is believed to be limited by the amounts dissolved in the water phase (Ogram et al., 1985; Rijnaarts et al., 1990; Volkering et al., 1992; Volkering et al., 1993; Harms and Bosma, 1997; Bosma et al., 1997), with sorbed, crystalline, and non-aqueous phase liquid (NAPL)-dissolved PAHs being unavailable to PAH-degrading organisms. Bioavailability is considered a dynamic process, determined by the rate of substrate mass-transfer to microbial cells relative to their intrinsic catabolic activity (Bosma et al., 1997; Harms and Bosma, 1997). It has been described by a bioavailability number, Bn, (Koch, 1990; Bosma et al., 1997), which is a measure of a microorganism’s substrate degradation efficiency in a given environment. Bn is defined as the capacity of an organism’s or a population’s environment to provide a chemical, divided by the capacity of the organism or population to transform that chemical. At high mass transfer rates, the overall biodegradation rate is controlled by the metabolic activity of the bacteria (Bn > 1), i.e. by both the specific activity of the cells and the population density. At Bn ¼ 1, the biodegradation rate is equally controlled by the physical transport and the microbial activity. When the transport of the substrate decreases or the bacterial population grows, the mass transfer becomes the factor that limits the biodegradation (Bn ! 1).
有关微生物的英语作文
有关微生物的英语作文Microorganisms: The Unseen Majority.Microorganisms, the microscopic organisms that inhabit all corners of our planet, play a vital role in the functioning of the Earth's ecosystems. These diverse and abundant life forms encompass bacteria, archaea, fungi, protists, and viruses, each with its unique characteristics and ecological significance.Ubiquity and Abundance.Microorganisms are ubiquitous, found in virtually every environment on Earth. They thrive in extreme conditions, from the scorching deserts to the icy depths of the ocean. Their abundance is staggering, with estimates suggesting that the total number of microorganisms exceeds the total number of stars in the observable universe.Diversity and Classification.The diversity of microorganisms is immense, spanning a vast array of species with distinct morphologies, metabolisms, and ecological roles. Bacteria and archaea, the prokaryotes, are the most abundant microorganisms, characterized by their lack of a nucleus and other membrane-bound organelles. Fungi, with their chitin-based cell walls, include yeasts, molds, and mushrooms. Protists, a diverse group of eukaryotic organisms, encompass algae, protozoa, and slime molds. Viruses, the smallest microorganisms, are acellular entities that rely on host cells for replication.Ecological Roles.Microorganisms play crucial ecological roles in various ecosystems. They participate in the decomposition of organic matter, releasing essential nutrients back into the environment. Nitrogen-fixing bacteria, for instance, convert atmospheric nitrogen into a form usable by plants, supporting plant growth and ecosystem productivity.Microorganisms also contribute to the cycling of carbon, phosphorus, and sulfur through the environment. Methanogens, archaea that produce methane, play a significant role inthe global carbon cycle. Mycorrhizal fungi form symbiotic relationships with plant roots, enhancing nutrient uptake and providing protection against pathogens.Beneficial Microbes.Many microorganisms are beneficial to humans and other organisms. Lactic acid bacteria, found in fermented foods like yogurt and kefir, promote gut health and aid digestion. Probiotics, live microorganisms with health-promoting effects, are widely used in dietary supplements and functional foods.Microorganisms also have industrial applications. Yeast is used in the production of bread, beer, and wine. Penicillium fungi are the source of penicillin, the first discovered antibiotic. Microbes are also employed in biotechnology, wastewater treatment, and bioremediation efforts.Pathogenic Microbes.While many microorganisms are beneficial, some are pathogenic, causing infections and diseases in humans, animals, and plants. Bacteria such as Salmonella and Escherichia coli can cause food poisoning. Viruses like influenza and HIV can lead to significant health problems. Fungi can cause infections such as athlete's foot and ringworm.Microbiome and Human Health.Research has highlighted the importance of the human microbiome, the community of microorganisms residing in and on our bodies. These microbes play a crucial role in immune function, digestion, and metabolism. Dysbiosis, an imbalance in the microbiome, has been linked to various health conditions, including obesity, diabetes, and inflammatory bowel disease.Antimicrobial Resistance.The overuse and misuse of antibiotics have led to the emergence of antimicrobial resistance, a major threat to global health. Bacteria that have developed resistance to multiple antibiotics are increasingly common, making it difficult to treat infections. The development of new antibiotics and alternative antimicrobial strategies is essential to combat antimicrobial resistance.Conclusion.Microorganisms are essential components of Earth's ecosystems, playing vital roles in nutrient cycling, decomposition, and symbiotic relationships. They also have significant implications for human health and well-being, both as beneficial microbes and pathogenic agents. As we continue to explore the vast and diverse world of microorganisms, we deepen our understanding of their ecological significance and their potential to shape our future.。
微生物翻译
Tracking the Elusive Viroid跟踪难以捉摸的类病毒According to accepted scientific dogma, the discovery of the viroid was not supposed to happen.根据人们已知的科学定义，类病毒是不可能存在的Finding out what causes potato spindle tuber disease brought about a small revolution in the study, diagnosis, and treatment of viral plant diseases. It also helped change approaches and attitudes in the study of livestock and human diseases.人们在寻找导致马铃薯纺锤块茎病原因的过程中，引发了一场植物病毒疾病的诊断和治疗的小革命。
它还改变了在牲畜和人类疾病的研究中的方法和态度。
But as crop diseases go, it wasn't very important. It didn't cost potato farmers millions of dollars in losses or control measures. Of course, if it got into a potato crop, it led to a second-year harvest of spindly, twisted tubers, but that didn't happen often.但随着作物疾病的离去，他变得并不重要。
因为它没有造成种植马铃薯的农民过多的损失。
当然一旦病毒进入了土豆，就会导致导致第二年收获细长,扭曲的块茎,但这并不经常发生。
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A/O法活性污泥中氨氧化菌群落的动态与分布摘要：我们研究了在厌氧—好氧序批式反应器（SBR）中氨氧化菌群落（AOB）和亚硝酸盐氧化菌群落（NOB）的结构活性和分布。
在研究过程中，分子生物技术和微型技术被用于识别和鉴定这些微生物。
污泥微粒中的氨氧化菌群落结构大体上与初始的接种污泥中的结构不同。
与颗粒形成一起，由于过程条件中生物选择的压力，AOB的多样性下降了。
DGGE测序表明，亚硝化菌依然存在，这是因为它们能迅速的适应固定以对抗洗涤行为。
DGGE更进一步的分析揭露了较大的微粒对更多的AOB种类在反应器中的生存有好处。
在SBR反应器中有很多大小不一的微粒共存，颗粒的直径影响这AOB和NOB的分布。
中小微粒（直径<0.6mm）不能限制氧在所有污泥空间的传输。
大颗粒（直径>0.9mm）可以使含氧量降低从而限制NOB的生长。
所有这些研究提供了未来对AOB微粒系统机制可能性研究的支持。
关键词：氨氧化菌（AOB），污泥微粒，菌落发展，微粒大小，硝化菌分布，发育多样性•简介在浓度足够高的条件下，氨在水环境中对水生生物有毒，并且对富营养化有贡献。
因此，废水中氨的生物降解和去除是废水处理工程的基本功能。
硝化反应，将氨通过硝化转化为硝酸盐，是去除氨的一个重要途径。
这是分两步组成的，由氨氧化和亚硝酸盐氧化细菌完成。
好氧氨氧化一般是第一步，硝化反应的限制步骤：然而，这是废水中氨去除的本质。
对16S rRNA的对比分析显示，大多数活性污泥里的氨氧化菌系统的跟ß-变形菌有关联。
然而，一系列的研究表明，在氨氧化菌的不同代和不同系有生理和生态区别，而且环境因素例如处理常量，溶解氧，盐度，pH，自由氨例子浓度会影响氨氧化菌的种类。
因此，废水处理中氨氧化菌的生理活动和平衡对废水处理系统的设计和运行是至关重要的。
由于这个原因，对氨氧化菌生态和微生物学更深一层的了解对加强处理效果是必须的。
当今，有几个进阶技术在废水生物处理系统中被用作鉴别、刻画微生物种类的有价值的工具。
目前，分子生物技术的应用能提供氨氧化菌群落的详细分类说明。
如今，主要由于其细胞固定策略，好氧污泥颗粒处理已经成为传统废水处理的替代工艺。
颗粒有更加彻底的紧密结构和快速适应速率。
因此，颗粒污泥系统比传统活性污泥法有更高的混合悬浮固体浓度浓度(MLSS)和更长的污泥龄(SRT)。
更长的污泥龄能提供足够长的时间让时代时间长的微生物生长(例如氨氧化菌)。
有些研究表示，硝化颗粒可以在富铵离子废水中培养出来，并且颗粒的直径很小。
其他研究报告说，大直径颗粒已经在序批式反应器(SBR)中人工合成的有机废水里培育出来了。
污泥颗粒里的大量不同微生物共存，并去除COD和氮磷。
然而，对于直径大于0.6mm的大颗粒来说，由于氧传递被限制不能到达颗粒核心，外部好氧壳和内部厌氧地带共存。
这些特性表明，大颗粒污泥内部环境不适合氨氧化菌的生长。
有些研究表明，颗粒大小和密度导致了氨氧化菌、亚硝酸氧化菌和反硝化菌的分布和优势种群。
虽然不少研究力求评估废水处理系统中氨氧化菌的生态生理，但是至今仍然被污泥颗粒化过程的水力学、分布、氨氧化菌群落的数量化限制着。
•原理和方法•反应器设置和操作污泥颗粒被接种在有效体积为4L的实验室规模的SBR里。
反应器有效直径和高度分别为10cm和51cm。
水力停留时间设为8h。
来自全尺寸污泥处理设置(中国天津污水处理厂)的活性污泥被作为反应器的种污泥，其MLSS初始浓度为3876mg/L。
反应器操作6小时为一循环，由2分钟的进水时间，90分钟厌氧混合，240反正抛弃阶段和5分钟出水阶段组成。
在20天80个SBR循环后，污泥沉降时间逐渐从10分钟降到5分钟，并且只有沉降速度大禹4.5m/h的颗粒才能在反应器中停留。
入流中的主要化合物包括NaAc(450mg/L)，NH4Cl(100mg/L)，(NH4)2SO4(10mg/L)，KH2PO4(20mg/L)，MgSO4·7H2O(50mg/L)，KCl(20mg/L)，CaCl2(20 mg/L)，FeSO4·7H2O(1mg/L)，pH 7.0-7.5，and 0.1 mg/L元素示踪剂。
分析方法-TOC、TN、TP、MLSS、SVI都根据标准方法定期检测。
污泥大小分布由筛法决定。
4个干净的直径为5cm钢制筛，筛孔直径分别0.9,0.6,0.45,和0.2mm，这4个筛子被全程监控。
用友刻度的圆柱从反应器中取100mL的污泥，然后放到0.9mm筛孔的筛子上。
随后用蒸馏水冲洗，直径小于0.9mm的颗粒通过这个筛子，到达筛孔更小的筛子上。
冲洗过程要重复几次，以分开污泥团。
不同面上收集到的颗粒恢复用蒸馏水反冲洗。
每一部分都手机在不同的烧杯里，然后用量化的滤纸过滤来测定TSS。
一旦留在各个筛子上TSS的数量确定了，就可以确定不同大小的颗粒占污泥总重的比例了。
•DNA提取和PCR-DGGE来自大约8mg的MLSS种的污泥被转化成 1.5mL的Eppendorf管，然后在14000g条件下离心10分钟。
移除上清液，向其中加入1mL磷酸钠缓冲液，然后在无菌条件下研磨以分离颗粒。
使用E.Z.N.A.Soil DNA工具，离心物种DNA染色体被分离。
为了放大氨氧化菌特征16s rRNA来进行DGGE，一个巢式PCR被用为先前描述。
30µl的巢式PCR放大剂被加载并被在聚丙烯酰胺凝胶上的加了线性分布为35%-55%的变性剂DGGE分开。
这个胶体在维持60度、140V、1×TAE缓冲液中(通用突变检测系统)运行 6.5h。
电泳结束后，银染色和胶体的发展表现正如Sanguinetti所表述。
接下来是空气干燥和用凝胶成像分析系统扫描。
凝胶扫描图像用Quantity One分析，版本号4.31。
成对群落相似性的色子指数是计算评估氨氧化菌群落在DGGE中线路相似性的。
这个用Quantity One测出的指数范围从0%(无共同频带)到100%(频带相同)。
Shannon多样性指数（H）是用来衡量将一个菌群中每个菌种的丰富度和比例加入考虑的微生物多样性。
H用下列等式计算：其中，ni/N表示i菌种占总群落的比例(i条带亮度在条带总亮度中的比例)。
微生物系统树图模板相似性使用Quantity One不用非加权配对组算术平均数（UPGMA法）算法就能计算出来。
突出的DGGE条带被切除并溶解在30mL Milli-Q水中过夜，温度维持4摄氏度。
在冷冻解冻3次后凝胶中的DNA被回收。
目标DNA片段的克隆及测序按照既定的方法（Zhang等，2010）进行。
•硝化细菌的分布为了调查AOB和NOB在颗粒中的空间分布，3种大小([0.2-0.45],[0.45-0.6],>0.9 mm)的颗粒在第180天被选定做FISH分析。
2mg的污泥样品被固定在在4摄氏度下的4％多聚甲醛溶液16-24 h，然后用磷酸钠缓冲液冲洗两次；样本分别在在50%，80%和100%的乙醇中脱水10分钟。
在室温下，将颗粒在乙醇—二甲苯体积比分别为3:1，1:1，1:3然后100%二甲苯的溶液中连续浸泡，每次10分钟后，颗粒中的乙醇然后完全被二甲苯取代。
随后，将颗粒在二甲苯与石蜡体积比为1:1的60度溶液中浸泡30分钟，接着再在100%石蜡溶液中浸泡30分钟，颗粒被石蜡嵌入。
在石蜡固化后，切为8mm厚的片，放置在涂了明胶的显微镜上。
将切片在二甲苯和乙醇中各浸泡30分钟，石蜡被去除，然后将切片干燥。
三个寡核苷酸探针被用于杂交：FITC标记为Nso190，指明了大多数AOB；TRITC标记为NIT3，指明了硝化sp。
所有的探针序列，杂交条件，以及洗涤条件都在表1中给出。
寡核苷酸的合成以及荧光标记都来自Takara公司。
杂交是在包含了各个标记了的探针(5ng µ/L)的46摄氏度度杂交缓冲液(0.9M NaCl,甲酰胺的百分比见表1，20mM Tris/ HCl，pH值8.0，0.01% SDS)下进行了2小时。
杂交后，未被结合的寡核苷酸由一个严格的洗涤步骤去除：在48度与洗涤液含有相同化合物的缓冲液中洗涤15分钟。
为了所有DNA的探测，DAPI被用甲醇最终稀释到浓度为1ng µ/L。
将切片用DAP-Iemethanol覆盖并保持恒温37度15分钟。
然后将切片用甲醇清洗一次，再用蒸馏水简单清洗，完了立刻空气干燥。
使用Vectashield(媒介实验室)以防止照片变白。
使用激光共聚焦显微镜来抓拍杂交图像(CLSM,Zeiss 710)。
每种颗粒大小的每个探头都各自一共拍了10张图像。
最后使用Adobe PhotoShop选出代表图像和最终图像的评价。
表1：用于不同大小颗粒的寡核苷酸探针图1：生物量和SVI10在整个操作过程中的变化•结果•SBR性能及颗粒特征在启动阶段，反应器能高效去除TOC以及氨氮。
98%的氨氮和100%的TOC分别在第3天和第5天从入流中被去除(图S2，S3)。
这一期间总氮和总磷的去除率不高，虽然总磷的去除率逐渐提高，在第33天达到100%(图S4)。
为了确定污泥颗粒的污泥体积指数，沉淀时间由10分钟代替30分钟，因为颗粒污泥在60分钟和5分钟后有一个相似的SVI数值。
接种污泥的SVI值是108.2Ml/g。
在连续操作中MLSS和SVI10的变化如图1所示。
污泥沉降性在设置阶段明显提升。
图2反应了污泥颗粒的慢速形成，从流动态到颗粒状态。
•DGGE技术分析：AOB的群落结构在污泥颗粒化中的变化巢式PCR的结果在图S1中显示。
在GSBR的操作中，较好显示的DGGE条带被在代表性点上得到，那些条带揭示AOB群落的结构在污泥颗粒化和稳定化过程中是动态的(图3)。
实验结束时的菌群结构与初始接种污泥的菌群结构是不同的。
AOB群落在第一天和GSBR操作的最后仅有40%的相似度，指明接种污泥和形成的颗粒污泥中AOB群落有重大变化。
通过计算Shannon指数H分析DGGE模板得出的生物多样性见图5.图2：污泥中颗粒大小分布在操作过程中的变化图3：AOB群落在污泥颗粒化过程中DGGE分析(顶部表示取样时间)。
主要条带已用数字标出(条带1-15)在污泥接种阶段(在第38天前)，指数H由于反应器中一些菌种的消失明显下降。
虽然几种接种污泥中的优势菌种(条带2,7,10,11)得以保留，但是许多条带削弱或消失了(条带3,4,6,8,13,14,15)。
在第45天后，多样性指数趋于稳定，并且显示流动性变小(从0.72到0.82)。
模板条带相似性利用UPGMA程序分析。
UPGMA分析显示三个组菌落群相似度约为67%-78%，群体内部约为44%-62%。
一般来说，第一组与污泥接种和冲刷有关，第二组与污泥颗粒化及SVI10值下降有关，第三组和稳定系统及优良的生物沉淀性有关。