chapter 5 enzyme
第五章 固定化酶和细胞
制备固定化酶的依据
1.固定化酶必须能保持酶原有的专一性、 1.固定化酶必须能保持酶原有的专一性、高效催化 固定化酶必须能保持酶原有的专一性 能力和常温、常压下能起催化反应等特点。 能力和常温、常压下能起催化反应等特点。 2.固定化酶应能回收、贮藏，利于反复使用。 2.固定化酶应能回收、贮藏，利于反复使用。 固定化酶应能回收 3.固定化酶应用于机械化和自动化操作 固定化酶应用于机械化和自动化操作， 3.固定化酶应用于机械化和自动化操作，所用载体 常有一定的机械强度。 常有一定的机械强度。 4.固定化酶应能保持甚至超过原有酶液的活性 固定化酶应能保持甚至超过原有酶液的活性。 4.固定化酶应能保持甚至超过原有酶液的活性。即 要保护活性中心基团。 要保护活性中心基团。 5.固定化酶应能最大程度与底物接近 固定化酶应能最大程度与底物接近， 5.固定化酶应能最大程度与底物接近，从而提高产 具有最小的空间位阻。 量。具有最小的空间位阻。 6.固定化酶应有最大的稳定性 固定化酶应有最大的稳定性。 6.固定化酶应有最大的稳定性。 7.固定化酶应易与产物分离 固定化酶应易与产物分离。 7.固定化酶应易与产物分离。
随着固定化技术的发展，出现固定化菌体 1973年 随着固定化技术的发展，出现固定化菌体 。1973年，日 本首次在工业上应用固定化大肠杆菌菌体中的天门冬氨 酸酶，由反丁烯二酸连续生产L 天门冬氨酸。 酸酶，由反丁烯二酸连续生产L-天门冬氨酸。 在固定化酶和固定化菌体的基础上，70年代后期出现了 在固定化酶和固定化菌体的基础上，70年代后期出现了 固定化细胞技术 技术。 1976年 固定化细胞技术。 1976年，法国首次用固定化酵母细胞 生产啤酒和酒精，1978年日本用固定化枯草杆菌生产淀 生产啤酒和酒精，1978年日本用固定化枯草杆菌生产淀 粉酶，开始了用固定化细胞生产酶的先例。 粉酶，开始了用固定化细胞生产酶的先例。 1982年 日本首次研究用固定化原生质体生产谷氨酸， 1982年，日本首次研究用固定化原生质体生产谷氨酸， 固定化原生质体生产谷氨酸 取得进展。固定化原生质体由于解除了细胞壁的障碍， 取得进展。固定化原生质体由于解除了细胞壁的障碍， 更有利于胞内物质的分泌， 更有利于胞内物质的分泌，这为胞内酶生产技术路线的 变革提供了新的方向。 变革提供了新的方向。
chapter-6-enzyme
②寡聚酶(oligomeric enzyme) 寡聚酶由几个甚至几十个亚基组成，亚基相同或不同，亚基 间以非共价键结合，用4 mol／L尿素溶液或其它方法可以把 它们彼此分开。 寡聚酶的相对分子质量从35 000到几百万。 例如磷酸化酶a和3-磷酸甘油醛脱氢酶等。
③多酶体系(multienzyme system)
全酶 = 酶蛋白 + 辅因子（辅酶、辅基、金属离子）
辅因子包括 辅酶（co-enzyme）
辅酶与酶蛋白结合较疏松（非共价键相连），可用透析或 超滤方法除去，一种辅酶可为几种酶的辅酶。
辅基（prosthetic group）
辅基与酶蛋白结合紧密（共价键相连），不易用透析或超滤 方法除去，需经化学处理才能将其与酶蛋白分开，辅基一 般为一种酶专有
酶的活性中心也称活性部位（active site），是指酶分子 中与底物结合并起催化反应的空间部位。 结合部位，由一些参与底物结合的有一定特性的基团组成 催化部位，由一些参与催化反应的基团组成，底物的键在 此处被打断或形成新的键，从而发生一定的化学变化。
5 酶活力测定及分离提纯 酶的活力测定
[P]
斜率=[P]/t=v t
酶的活力单位(enzyme activity unit，U),酶活力单位 是酶活力大小或酶量的量度。在一定条件下，一定时间 内将一定量的底物转化为产物所需的酶量。
1961年，酶学委员会规定：1个酶活力单位(IU，国际单 位)，是指在最适条件(温度25℃)下，每分钟内催化1微 摩尔(μmol)底物转化为产物所需的酶量。
B
CH2OH H C HO C H C H C
O
H OH OH
CH2O
P
CH2O
生化--英文题
生化历来都不画重点的，但留学生老是过不了，于是就有了这个重点资料，和我们考的差不多，但是英语的，求高人翻译啊Brief Exercises of BiochemistryChapter 1 The structure and function of proteinExplain the following terms1. peptide bond2. Amino acid residues3. Primary structure of protein4. isoelectric point5. Secondary structure of protein6. Tertiary structure of protein7. Domain8. Protein denaturation9. Quaternary structure of proteinAnswer the following questions briefly1. What is physiological significance of hemoglobin oxygen dissociation curve as S-shaped?2. Please describe physiological functions of proteins.Discuss the following questions (Essay questions)1. Explain the relationship between the primary and spatial structure and the function of protein.Chapter 2 The structure and function of nucleic acidsExplain the following terms1. primary structure of nucleic acids2. DNA denaturation3. Tm4. DNA renaturation5. nucleic acid hybridizationAnswer the following questions briefly1. What is the structural characteristics of an eukaryocyte mature mRNA?2. What is the biological significance of Tm?Discuss the following questions (Essay questions)1. Please compare the two types of nucleic acids (DNA and RNA) in the chemical composition, molecular structure, cell distribution and biological functions.2. Please describe the structural characteristics of the B-DNA.3. Describe the molecular composition, structural features and functions of tRNA.Chapter 3 EnzymeExplain the following terms1. enzyme2. enzyme active center3. enzyme competitive inhibition4. Km5. isoenzyme6. zymogen activationAnswer the following questions briefly1. Explains with examples the competitive inhibition characteristic and the practical significance.2. What is the relationship between the enzyme cofactor and vitamine?3. What is the physiological significance of zymogen?4. What is isoenzyme? What is clinical significance of isoenzyme?5. How many kinds of essential group of enzyme are there? What is the role of each?Chapter 4 Metabolism of carbohydrateExplain the following terms1. glycolysis2. glycolytic pathway3. tricarboxylic acid cycle4. gluconeogenesis5. blood sugarAnswer the following questions briefly1. Describe briefly source and fate of blood sugar2. Describe briefly the physiological significance of gluconeogenesis3. Describe briefly the physiological significance of glycolysis4. Describe briefly the outline of TCA cycle5. Describe briefly the physiological significance of TCA cycle6. Describe briefly the physiological significance of pentose phosphate pathway7. Outline the reasons for the formation of lactic acid cycle and the physiological significance.8. Overview the important role of B vitamins in glucose metabolism.9. Why 6-phosphate glucose dehydrogenase activity will increase after uptake high-carbohydrate diet?Discuss the following questions (Essay questions)1. Explain how is lactate converted into glucose? (Write down the main reactions and key enzymes)2. Explain how is lactate converted into CO2, H2O and releases ATP? (Write down the main reactions and key enzymes)3. Overview the regulation molecular mechanism of adrenaline on the blood sugar level.4. Please explain why a slimmer has to reduce the intake of carbohydrates from the point of view of nutrients metabolism. (Write down the related pathways, cellular localization, main reactions and key enzyme)Chapter 5 Metabolism of lipidsExplain the following terms1. fat mobilization2. ketone body3. plasma lipoprotein4. apolipoprotein5. essential fatty acid6. blood lipidsAnswer the following questions briefly1. What is the function of bile acid at lipids digestion?2. What is the physiological significance of ketone body generation?3. What are materials of fatty acid synthesis?4. What is the physiological significance of cholesterol?5. What are the functions of apolipoprotein?Discuss the following questions (Essay questions)1. Describe the sources, chemical composition characteristics and main physiological functions of plasma lipoprotein.2. Explain how is the stearic acid converted into CO2, H2O and releases ATP?3. Please describe the oxidation catabolism process of glycerol generated from fat mobilization4. Explain how is the glycerol converted into glycogen?5. Describe the source and fate of acetyl-CoA?Chapter 6 Biological oxidationExplain the following terms1. biological oxidation2. respiratory chain3. oxidative phosphorylation4. substrate level phosphorylationDiscuss the following questions (Essay questions)1. Write down the sequence of two respiratory chainChapter 7 Metabolism of amino-acidExplain the following terms1. essential amino acid2. deamination of amino acid3. transamination of amino acid4. one carbon unit5. hyperammonemiaAnswer the following questions briefly1. What is the physiological significance of one carbon units?2. What is meaning of PAPS, GABA, SAM and FH4 each?3. Write down the deamination of amino acids in vivo.4. Outline the source and fate of blood ammonia.Discuss the following questions (Essay questions)1. How does a glutamate be oxidized to supply energy? What is the final product?2. What are functions of vitamins B in the metabolism of amino acids?3. Use the alanine as an example, try to explain the gluconeogenesis process of glucogenic amino acids.Chapter 8 Metabolism of nucleotideExplain the following terms1. de novo synthesis pathway of purine nucleotide2. nucleotide antimetaboliteAnswer the following questions briefly1. Outline the biological function of nucleotide.2. Outline the physiological significance of salvage synthesis of purine nucleotide.Discuss the following questions (Essay questions)1. Use the 6-mercaptopurine as an example, please explain the mechanism of antimetabolite.Chapter 10 Biosynthesis of DNAExplain the following terms1. semi-conservative replication2. reverse transcription3. replication4. excision repairing5. frame-shift mutationAnswer the following questions briefly1. Outline the classification and function of prokaryote DNA polymerase.2. Outline the classification and function of eukaryote DNA polymerase.3. Outline the factors causing DNA damage.4. Outline the repairing of DNA damage.5. Outline the central dogma.Discuss the following questions (Essay questions)1. Describe the materials involved in prokaryote DNA replication and their functions in that process.2. Describe the biological significance of mutation.Chapter 11 Biosynthesis of RNAExplain the following terms1. transcription2. posttranscriptional process3. hnRNA4. promoter5. ribozyme6. structure geneAnswer the following questions briefly1. Outline the eukaryote posttranscriptional process.2. Outline the products of three kinds of eukaryote RNA polymerases.Discuss the following questions (Essay questions)1. Describe the similarity and dissimilarity of replication and transcription.Chapter 12 Biosynthesis of proteinExplain the following terms1. translate2. polyribosomes3. genetic code4. degeneracy of codonAnswer the following questions briefly1. Describe briefly the RNAs involved in the protein synthesis and their functions in that process.2. Outline the main features of the genetic code.3. Describe briefly the dissimilarity of translation initiation complex formation of prokaryotes and eukaryotes.Discuss the following questions (Essay questions)1. Describe the materials involved in protein biosynthesis and their functions in that process.3. Please comparing the process of translation of prokaryotes and eukaryotes.Chapter 13 The regulation of gene expressionExplain the following terms1. gene expression2. cis-acting element3. trans-acting factor4. operon5. general transcription factor6. enhancerAnswer the following questions briefly1. What is biological significance of regulation of gene expression?2. Outline the function of each component of operon.3. What characteristics does eukaryotic genome structure have?Discuss the following questions (Essay questions)1. Explain the regulation mechanism of lactose operon.Chapter 14 Gene recombination and gene engineeringExplain the following terms1. restriction endonuclease2. genomic DNA3. vector4. cDNA. library5. genetic engineering6. DNA cloning7. homologous recombinationAnswer the following questions briefly1. What are the main selection criteria of gene vector?2. What is the significance of restriction endonuclease of bacteria themselves?3. At present, How many ways to get target genes?4. Outline the basic process of DNA cloning.Discuss the following questions (Essay questions)1. Why plasmid can be used as the vector of genetic engineering?2. Explain how to connect the foreign gene and the vector.3. What is α-complementary? Explain how to screening recombinant by it using an example.Chapter 15 Cellular signal transductionExplain the following terms1. signal transduction2. receptor3. ligand4. signal transduction pathway5. protein kinase6. second messenger7. G proteinAnswer the following questions briefly1. Describe briefly which protein kinases are regulated by intracellular second messenger.2. Outline the classification of receptor and its chemical signals.3. Describe briefly the basic mode of G protein-coupled receptor (seven transmembrane receptor)-mediated signal transduction.4. Describe briefly the signal transduction pathway of intracellular receptor of steroid hormone.Discuss the following questions (Essay questions)1. How does intracellular receptor play its function?2. Explain the process of the glycogen metabolism regulated by glucagon.3. Use fat mobilization as an example, explain the process of cAMP-protein kinase pathway. Chapter 16 Blood biochemistryExplain the following terms1. 2, 3-BPG shuntAnswer the following questions briefly1. Outline the function of plasma protein.Chapter 17 Liver biochemistrExplain the following terms1 biotransformation 2. primary bile acid 3. secondary bile acid4. bile pigment5. jaundiceAnswer the following questions briefly1. Describe briefly the physiological significance of biotransformation.2. Outline the main physiological functions of bile acids.3. Describe briefly production and blood transportation of bilirubin.Discuss the following questions (Essay questions)1. Describe the influence factor of biotransformation.2. Explain the dissimilarity of unconjugated and conjugated bilirubin.Chapter 18VitaminsExplain the following terms1. vitamin2. lipid-soluble vitamin3. water-soluble vitaminAnswer the following questions briefly1. Outline the biochemical function of vitamin E.2. Describe briefly the biochemical function of vitamin D and its deficiency disease.Discuss the following questions (Essay questions)1. Explain the relationship between the water-soluble vitamin and the coenzyme. Chapter 20 Oncogenes, tumor suppressor genes and growth factorExplain the following terms1. oncogene2. proto-oncogene3. tumor suppressor geneAnswer the following questions briefly1. Describe characteristics of proto-oncogene.2. Describe briefly wild-type p53 tumor suppressor gene mechanism.Chapter 21 The Principle and Application of Common Used Techniques in Molecular Biology Explain the following terms1. probe2. PCR3. Gene diagnosis4. gene therapyDiscuss the following questions (Essay questions)1. Describe the definition, type and application of the blotting technique.2. Describe the PCR reaction principle and the basic steps.。
4 酶 (Enzyme)
5）酶的转换数：
酶的转化数(turnover number，即kcat)是 它的最大催化活性的一种量度。 kcat定义为： 当酶被底物饱和时,每分子的酶在单位时间内 催化底物分子转变成产物的数量。转换数也称 为酶的分子活性(molecular activity)。
对于在简单的米-曼氏方程情形下(只有 一种ES复合物),假定反应混合物中的酶浓度 ([ET]或[E0])是已知道, 在饱和的[S]下,
一. 命名原则 1、习惯命名 例如：乙醇脱氢酶 2.、系统命名的原则 ●应标明酶的所有底物及催化的性质，并用︰ 符号把底物分开。例如：乙醇︰NAD+脱氢酶. ●不管催化正反应还是逆反应，一般都用同一 名称。 ●如果所催化的反应包含二种变化，则尽可能 用同一种变化来表示，另一个功能附后。例如： L-谷氨脱氢酶催化的反应是：该酶的系统命名 是 谷氨酸︰NAD+脱氢酶（脱氨）。
该酶的系统命名是 谷氨 酸︰NAD+脱氢酶（脱氨）
二、酶的分类
1、氧化还原酶类: 催化氧化还原反应 A· + B → A + B· 2H 2H
这类酶包括需氧 脱氢酶、氧化酶 和不需氧脱氢酶
2、转移酶类：催化功能基团的转移反应（插 入4-2b）： AB + C ←→A + BC
3、水解酶类:催化水解反应： AB + HOH →AOH + BH （可视为一类特殊的转移酶）
③对于讨论酶的催化效率来说，最有用的参
数应该包含kcat和Km两者。 根据米氏方程的推导
2、pH对酶促反应的影响 酶作用环境的pH可以影响酶蛋白的结构﹑ 酶活性部位的解离状态﹑辅酶的解离以及底物 分子的解离，从而影响酶与底物的结合以及对 底物的催化效力。 一般来说，酶只在一个有限的pH范围内是 活泼的。大多数酶只有在某一特定的pH条件下， 它 的 催 化 活 性 是 最 大 的 。 这 一 pH 称 为 最 适 pH （pH optimum）。
chapter 5 enzyme(2010)-酶
Amylase
Enzyme -Amylase -Amylase Glucoamylase Configuration of glucoside bond or substance -1,4（endo-splitting） -1,4（exo-splitting , start from non-reducing end） -1,4/ -1,6/ -1,3（exosplitting ， start from nonreducing end） Product dextrine and reductive sugar （） maltose（ ） glucose（ ）
Debranching Enzyme
Cyclodextrin glycosyltransferase
-1,6 (amylopectin)
starch - or -cyclodextrines
Method of enzymolysis
-Amylase
Method
Hydrolyze the interior -1,4-glucosidic bonds of starch (amylose and amylopectin), glycogen, and cyclodextrins with retention of - configuration of the anomeric carbon.
Chapter Ⅴ
Enzymes
Key points
Enzymatic Browning (酶促褐变) Enzymes used in food processing (食品加工中的酶)
Definition
Enzymes are proteins with catalytic activity due to their power of specific activation and conversion of substrates to products.
Chapter 5 固定化技术及其应用
Chapter 5 固定化技术及其应用Section 1 固定化技术1、发展历史：1953年，德国的格鲁布霍费（Grubhofer）和施莱思（Schleith）首次制成固定化酶。
1969~1973年，日本的千畑一郎首次在工业生产上连续生产L-氨基酸、L-天冬氨酸，开创了固定化酶和固定化微生物细胞应用于工业生产的先例；1976年，法国首次用固定化酵母细胞生产啤酒和酒精。
1978年，日本固定化枯草杆菌细胞生产α-淀粉酶的研究取得成功。
1986年，我国用固定化枯草杆菌原生质体生产碱性磷酸酶，用固定化黑曲霉原生质体生产葡萄糖氧化酶，用谷氨酸棒杆菌原生质体生产谷氨酸脱氢酶。
2、优势固定化细胞和固定化原生质体以酶等各种代谢产物的生产为目的，可以代替游离细胞进行酶的发酵生产，具有提高产酶率、缩短发酵周期并可连续发酵生产等优点，在酶的发酵生产中有广阔的发展前景。
3、现状在工业上使用的固定化酶还仅限于葡萄糖异构酶、葡萄糖氧化酶和青霉素酰化酶等为数不多的十几个酶种，仍需大力研究开发使更多的固定化酶和细胞能适用于工业规模生产。
Section 2 酶的固定化为了解决酶的稳定性较差、酶的一次性使用、酶的分离纯化等困难，获得的改善方法之一就是固定化技术的应用。
固定化酶（Immobilized Enzyme）：固定在一定载体上并在一定的空间范围内进行催化反应的酶。
酶的固定化：采用各种方法，将酶与水不溶性载体结合，制备固定化酶的过程。
（一）制备方法固定化酶的制备方法很多，常用的有吸附法、包埋法、结合法和交联法。
根据酶自身的性质、应用目的、应用环境来选择固定化载体和方法。
1）吸附法（adsorption）：利用各种固体吸附剂将酶吸附在其表面上固定的方法，是固定化中最简单的方法。
可分为物理吸附法和离子吸附法。
◆物理吸附法（physical adsorption）：通过物理方法将酶直接吸附在水不溶性载体（纤维素、淀粉、面筋、活性炭、多孔玻璃、硅胶等）表面而使酶固定化的方法，是制备固定化酶最早采用的方法。
药理学医学英语词汇.
协同作用 治疗效应 治疗指数 阈浓度 毒性反应
Chapter 3 Pharmacokinetics
英文 absorption active transport apparent volume of distribution(vd) bioavailability biotransformation blood-brain-barrier clearance, cl distribution drug transport rate elimination enzyme inducer enzyme inhibitor first order kinetics first-pass effect half life( t1/2) hepatoenteral circulation maintenance dose metabolism one-compartment model passive diffusion peak concentration (cmax ) placental barrier redistribution of drugs steady state concentration(css ) Plateau concentration time-concentration curve two-compartment model zero order kinetics
中文 卡巴胆碱 胆碱酯酶抑制剂 胆碱受体激动剂 调节麻痹 调节痉挛 加兰他敏 新斯的明 毒扁豆碱 毛果芸香碱 有机磷酸酯类 胆碱酯酶复活剂
Chapter 7 Cholinoceptor blocking drugs
英文
anisodamine
atropine
homatropine
pirenzepine
外研社2024_通用学术英语综合教程_读写__电子课件Chapter_5大学英语IV_5-2-Jin
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Passive voice
Controlling perspectiveWho is the sentence about?Topic (beginning: old information) + stress (ending: new information)No top-heavy passive sentenceDo not write sentences with very long subjects + a short passive verbe.g., The studies showing that laptop use can negatively affect performance on educational assessment when the computer is used for its intended function of easier note taking were reported in this article.
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Describing a process
Before You Read
While You Read
After You Read
Language Focus
Academic Literacy Skills
Reading 2
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While You Read
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were excluded
were disconnected
were preset
were projected
生物化学简明教程 第四版 第五章 酶
酶催化作用的机理
活化分子（处于过渡态的分子） 活化能
中间产物学说
降低反应所需的活化能
E+S
ES
EP
P+E
中间络合物的证据
过氧化物酶
H2O2 + AH2
A + 2H2O
E E+H2O2 E+H2O2+AH2
光谱吸收带
645 583 561 548 530 498
++
+
+
+
+
++
+
+
E：过氧化物酶
2．转移酶类（transferases）
催化基团的转移
AR+ B
A +BR
例：
谷丙转氨酶（GPT）（EC 2.6.1.2，L-丙氨酸：α—酮戊二酸氨基转移酶）
3．水解酶类（hydrolases）
AB + H2O 例：
A·OH + BH
α-葡萄糖苷酶
4．裂合酶类（lyases）
从底物移去一个基团而形成双键或逆反应
活性中心中的基团，在一级结构中可能相距较远
Active sites may include distant residues. (A) Ribbon diagram of the enzyme lysozyme with several components of the active site shown in color. (B) A schematic representation of the primary structure of lysozyme shows that the active site is composed of residues that come from different parts of the polypeptide chain.
5酶
1)用量少而催化效率高，只参加化学反应速度，不 参加化学反应 2)它能够改变化学反应的速度，但是不能改变化学 平衡常数 3)酶只能够本身能够发生的反应进行，反之则不行
二、酶的生物催化特点
（一）高效性
酶的催化作用可使反应速度比非催化反应提高107 -1020 倍。比其他催化反应高107 -1要内容
酶的一般概念 酶的组成与辅酶 酶结构与功能的关系 酶催化机理 酶促反应动力学 酶活性调节
第一节 酶的一般概念
酶的概念 酶的分类和命名 酶催化活性表示法 酶的特征
一、酶的概念
什么是酶（enzyme）？
酶是生物催化剂。绝大部分酶是蛋白质，还有一些核 糖核酸RNA具有催化作用，称为核酶（ribozyme）。
酶的转换数：Kat指每秒钟每个酶分子转换底物的
mmol数，代表酶的催化效率。
酶的活力单位（U）：酶活力的度量单位。1961年国
际酶学委员会规定：1个酶活力单位是指特定条件下，在1 分钟内能转化1umol底物的酶量。
酶比活性（enzyme specific activity）:每毫克酶
制剂所含的酶的国际单位数。用于比较每单位重量酶蛋白 的催化能力。比活性愈高表明酶愈纯
第二节 酶的组成和辅酶
一、简单酶（ simple enzyme）单纯由氨基酸组
成。如脲酶、胃蛋白酶、淀粉酶等
二、结合酶（conjugated enzyme）
结合酶（全酶）= 蛋白质部分（酶蛋白）+ 非蛋白质部分（辅因子）
酶的辅助因子: 本身无催化作用，在酶促反应中起 运
输电子、原子或某些功能基团的作用，包括金属离子和辅 酶（基）
一）酶的命名
1 习惯命名——依据所催化的底物（substrate）、反应的 性质、酶的来源等命名。例如淀粉酶，胃蛋白酶、碱性磷 酸酶。
生化英文名词解释
名词解释Glossary第一章蛋白质的结构与功能Chapter 1 Structure and Function of Proteinpeptide bond（肽键）：a covalent bond linking the α- amino group of one amino acid and theα-carboxyl group of another in a protein molecule.peptide（肽）：a molecule containing two or more amino acids linked by peptide bond. primary structure of protein（蛋白质的一级结构）：the amino acid sequence of a polypeptide.secondary structure of protein（蛋白质的二级结构）：the spatial arrangement of local portions of a polypeptide chain.tertiary structure of protein（蛋白质的三级结构）：the spatial arrangement of all the atoms of a protein or a subunit.quaternary structure of protein（蛋白质的四级结构）：the spatial arrangement of a protein that consists of more than one folded polypeptide chain or subunit.subunit（亚基）：an individual polypeptide chain that associates with one or more separate chains to form a complete protein.motif（模序）：a substructure formed with two or more secondary-structure peptide segments that are drawn close to each other.domain（结构域）：a region within a protein, particularly within a large polypeptide, that functions in a semi-independent manner.positive cooperativity（正协同效应）：an effect that the binding of one ligand to a protein facilitates the subsequent ligand binding.allosteric effect（变构效应）：an effect that a small molecule, called an effector, noncovalently binds to a protein and alters its activity.isoelectric point（pI）of protein （蛋白质的等电点）：the pH at which a protein has an equal number of positive and negative charges and hence bears no net charge. denaturation of protein（蛋白质变性）： the disruption of the natively folded structure of a protein caused by exposure to heat, radiation, or chemicals, or change in pH, that leads to an alteration of chemical, physical and biological properties of the第二章核酸的结构与功能Chapter 2 Structure and Function of Nucleic Aciddenaturation of DNA（DNA的变性）：the disruption of the native conformation of DNA by separation of the DNA double helix into its two component strands, due to heat, chemicals, or change in pH, etc.hyperchromic effect（增色效应）：the increase in ultraviolet absorbance of a DNA while the DNA is denatured.melting temperature（Tm, 融解温度）：the temperature corresponding to half the maximal increase in ultraviolet absorbance of a thermally denatured DNA.annealing（退火）：the process of returning a thermally denatured DNA to its original native structure when it is cooled gradually.第三章酶Chapter 3 Enzymessimple enzyme（单纯酶）：an enzyme that consists of only polypeptide chain(s). conjugated enzyme（结合酶）：an enzyme with its polypeptide portion(apoenzyme) linked to one or more substance other than amino acids, such as metals or small organic molecules.holoenzyme（全酶）：a complete enzyme consisting of the apoenzyme portion plus the cofactor component.essential group（必需基团）： a chemical group on the side chain of amino acid residue of an enzyme that is closely related to the activity of the enzyme.active center / active site（活性中心）：the region of an enzyme molecule that contains the substrate binding site and the catalytic site for converting the substrate(s) into product(s).activation energy（活化能）：the threshold energy that must be overcome to produce a chemical reaction.absolute specificity（绝对特异性）：the extreme selectivity of an enzyme that allows it to catalyze only the reaction with a single substrate in the case of a monomolecular reaction, or the reaction with a single pair of substrates in the case of a bimolecularrelative specificity（相对特异性）：the relative selectivity of an enzyme that allows it to catalyze the reaction with one type of reactants or one type of chemical bond. stereospecificity（立体异构特异性）：the selectivity of an enzyme for a particular stereoisomer.zymogen（酶原）：the inactive precursor of an enzyme.zymogen activation（酶原激活）：the process in which a zymogen is converted to an active enzyme by limited proteolysis and subsequently the active center of the enzyme is formed or exposed.isoenzyme（同工酶）：multiple forms of an enzyme that catalyze the same reaction but differ from one another in one or more of the properties, such as structural, physical, chemical and even immunological properties.第四章糖代谢Chapter 4 Carbohydrate Metabolismglycolysis（糖酵解）： the anaerobic degradation of carbohydrate whereby a molecule of glucose is converted to two molecules of lactic acid.substrate-level phosphorylation（底物水平磷酸化）：the synthesis of ATP from ADP by the phosphorylation of ADP coupled with exergonic breakdown of a high-energy organic substrate molecules.Pastuer effect（巴斯德效应）：the phenomenon that the glycolytic pathway is inhibited under aerobic conditions.glycogen（糖原）： a highly branched polymer of glucose residues primarily in 1,4 linkage but with 1,6 linkage at branchpoints.gluconeogenesis（糖异生）： the synthesis of glucose or glycogen from noncarbohydrate molecules, i.e., lactic acid, glycerol, glucogenic amino acids, etc.第五章脂类代谢Chapter 5 Lipid Metabolismessential fatty acids（必需脂肪酸）： the fatty acids, including linoleic acid, linolenic acid, and arachidonic acid, which can not be synthesized in the mammalian body and must be obtained from diet.mobilization of fat（脂肪动员）： a process of lipolysis in which the fat stored in adipose tissues is converted to free fatty acids and glycerol, which are consequently released into blood so that they can be used in other tissues.β-oxidation of fatty acid（脂肪酸的β-氧化）： a process in which a fatty acid is degraded through a sequential removal of two-carbon fragments from the carboxyl end and therefore acetyl CoA is formed as the bond between the α- and β-carbon atoms is broken.ketone bodies（酮体）： a group of molecules, i.e., acetone, acetoacetate, and β–hydroxybutyrate, that are synthesized in the liver from acetyl CoA.第六章生物氧化Chapter 6 Biological Oxidationrespiratory chain （呼吸链）/ electron transfer chain（电子传递链）： a series of electron carriers responsible for the transport of reducing equivalent from metabolite to molecular oxygen, with the net results of capturing energy for use in ATP synthesis, and of the reduction of oxygen to water.P/O ratio（P/O比值）： the number of molecules of Pi consumed in ATP formation for each oxygen atom reduced to H2O.oxidative phosphorylation（氧化磷酸化）： the process in which the phosphorylation of ADP to yield ATP is coupled to the electron transport through respiratory chain. uncoupler（解偶联剂）： a molecule, such as dinitrophenol, that uncouples ATP synthesis from electron transport.第七章氨基酸代谢Chapter 7 Amino Acid Metabolismessential amino acids（必需氨基酸）： the amino acids，including valine, leucine, isoleucine, threonine, phenylalanine, tryptophan methionine and lysine, that cannot be synthesized by animal body and must therefore be supplied by diet. transdeamination（联合脱氨基作用）： the coupled action of an aminotransferase and a glutamate dehydrogenase involved in deamination of the majority of amino acids. transamination（转氨基作用）： a reaction catalyzed by an aminotransferase, in which an amino group is transferred from an amino acid to a keto acid.ketogenic amino acids（生酮氨基酸）： the amino acids that can be converted to ketone bodies, i.e., leucine and lysine.glucogenic and ketogenic amino acids（生糖兼生酮氨基酸）： the amino acids, i.e., isoleucine, phenylalanine, tyrosine, threonine and tryptophan, that can be converted to either ketone bodies or carbohydrates.one carbon units（一碳单位）/ one carbon groups（一碳基团）： organic groups, including methyl(—CH3), methylene(—CH2—), methenyl(—CH＝), formyl(—CHO) and formimino(—CH＝NH) groups, each containing only one carbon atom generated through catabolisms of some amino acids.第八章核苷酸代谢Chapter 8 Nucleotide Metabolismthe de novo pathway of nucleotide synthesis（核苷酸的从头合成途径）： a pathway through which nucleotides are synthesized by using simple molecules, such as ribose 5-phosphate, amino acids, one carbon units and carbon dioxide.the salvage pathway of nucleotide synthesis（核苷酸的补救合成途径）： a pathway through which nucleotides are synthesized by using the existing nitrogenous bases or nucleosides.第九章物质代谢的联系与调节Chapter 9 Integration and Regulation of Metabolismkey enzyme（关键酶）/ pacemaker enzyme（限速酶）/ regulatory enzyme（调节酶）：an enzyme that sets the rate for the entire biochemical pathway, usually catalyzes the slowest and irreversible step, and can be regulated by a number of metabolites and effectors in addition to its substrates.allosteric regulation（变构调节）： a regulatory mechanism through which a specific low-molecular-weight molecule, called an effector or a modulator, noncovalently binds to a regulatory site outside the active center of a regulatory enzyme and alters the conformation and activity of the enzyme.chemical modification（化学修饰调节）： a regulatory mechanism through which enzyme activities are regulated by means of reversible interconversion between the active and inactive forms of the enzyme resulted from enzyme-catalyzed covalent modificationto a specific amino acid residue.第十章 DNA的生物合成（复制）Chapter 10 Biosynthesis of DNA (Replication)replication（复制）：a process in which an exact copy of parental DNA is synthesized by using each polynucleotide strand of the parental DNA as templates. semiconservative replication（半保留复制）： duplication of DNA after which the daughter duplex carries one parental strand and one newly synthesized strand.DNA polymerase（DNA聚合酶）：any of various enzymes, with the full name of DNA dependent DNA polymerase, that catalyzes the formation of polynucleotides of DNA using an existing strand of DNA as a template.point mutation（点突变）：a mutation that causes the replacement of a single base pair with another, including nonsense mutation, missense mutation and silent mutation. frameshift mutation（框移突变）：a mutation of insertion or deletion of a genetic material that leads to a shift in the translation of the reading frame, resulting in a completely different translation.reverse transcriptase（逆转录酶）：any of various enzymes, with the full name of RNA dependent DNA polymerase, that catalyzes the formation of polynucleotides of DNA using an existing strand of RNA as a template.telomeres（端粒）： structures that occur at the ends of eukaryotic chromosomes that prevent the unraveling of DNA.第十一章 RNA的生物合成（转录）Chapter 11 Biosynthesis of RNA (Transcription)RNA polymerase（RNA聚合酶）：any of various enzymes, with the full name of DNA dependent RNA polymerase, that catalyzes the formation of polynucleotides of RNA using an existing strand of DNA as a template.promoter（启动子）： a DNA sequence immediately before a gene that is recognized by RNA polymerase and signals the start point of transcription.intron（内含子）： a noncoding intervening sequence in a split or interrupted gene that is missing in the final RNA product.exon（外显子）： the region in a split or interrupted gene that codes for RNA which endup in the final product (e.g., mRNA).ribozyme（核酶）：ribonucleic acid with catalytic ability whose substrate is ribonucleic acid.第十二章蛋白质的生物合成（翻译）Chapter 12 Biosynthesis of Proteins (Translation)reading frame（阅读框）： a group of three nonoverlapping nucleotides that is read asa codon during protein synthesis. The reading frame begins with the initiator codonAUG.molecular chaperon (分子伴侣)：a sort of intracellular conservative protein, which can recognize the unnatural conformation of peptide and assist in the accurate folding of domains or the whole protein.signal peptide（信号肽）： a sequence of amino acid residues located at the N-terminal portion of a nascent secretory protein, which marks the protein for translocation across the rough endoplasmic reticulum.第十三章细胞信息转导Chapter 13 Cell Signalingprimary messenger（第一信使）： an extracellular signaling molecule that is released from the signaling cell and can regulate the physiological activity of the target cell.secondary messenger（第二信使）： a small intracellular molecule, such as Ca2+,cAMP, cGMP, diacylglycerol (DAG), inositol triphosphate (IP3), ceramide, or arachidonic acid (AA), etc., that is formed at the inner surface of the plasma membrane in response to a primary messenger.receptor （受体）： a molecular structure on the surface or interior of the target cell that specifically binds signaling molecule and initiates a response in the cell. ligand（配体）： a biologically active molecule that can bind to its specific receptor.G protein （G蛋白）/ guanylate binding proteins （鸟苷酸结合蛋白）：a trimeric guanylatebinding protein in the cytoplasmic side of plasma membrane that acts as a switch to turn activities on and off by interconversion between its monomeric GTPase andtrimeric GDP binding form.hormone response element （激素反应元件，HRE）：a specific DNA sequence that binds hormone-receptor complex; The binding of a hormone-receptor complex either enhances or diminishes the transcription of a specific gene.第十四章血液的生物化学Chapter 14 Biochemical Aspects of Bloodnon-protein nitrogen（非蛋白氮）：nitrogen contained in urea, creatine, creatinine, uric acid, bilirubin, and ammonia.acute phase protein（急性时相蛋白质）：a protein whose plasma concentration can be altered when acute inflammation or a certain type of tissue damage occurs.2,3-bisphosphoglyerate shunt（2,3-二磷酸甘油支路）：the pathway in erythrocyte glycolysis in which glycerate 1,3-bisphosphate(1,3-BPG) is isomerized to 2,3-bisphosphoglyerate(2,3-BPG) and the latter is consequently hydrolyzed to form 3-phosphoglycerate. The importance of 2,3-BPG in the erythrocyte lies in its ability to alter the extent to which hemoglobin binds with oxygen.第十五章肝的生物化学Chapter 15 Biochemical Aspects of the Liverbiotransformation（生物转化）： a series of enzyme-catalyzed processes through which non-nutritional molecules, which are usually hydrophobic, are converted into more soluble metabolites.jaundice（黄疸）： a clinical manifestation of hepatic disease, featuring yellow discolration of the plasma, skin, and mucous membranes, caused by bilirubin accumulation and staining.欢迎您的下载，资料仅供参考！致力为企业和个人提供合同协议，策划案计划书，学习资料等等打造全网一站式需求。
第五章酶的固定化
收率 Yield (%)
(fold)
2736.9
13080.2 23314.100
30 10 9
Sepharos
e柱层析 HiTrap19 42218 0.3
Q柱层析
实验 木瓜蛋白酶的固定化
实验原理：
载体：尼龙
固定化方法：共价结合法
Enzyme+N, N-甲叉双丙稀酰胺, 丙稀酰胺
引发剂－－inactiation
2）半透膜包埋法（微囊型）
将酶或含酶细胞包埋在高分子半透膜中的固定化方
法。
界面聚合法
是用化学手段制备微囊的方法。利用亲水性单体和
疏水性单体在油水界面上发生聚合反应形成聚合体
而将酶包裹起来。
（3）结合法
1）共价结合法 ☆ 通过共价键将酶与载体结合的方法。 ① 结合方法
化的方法称为包埋法。
凝胶包埋法（网格型） 包埋法 半透膜包埋法（微囊型）
只适合作用于小分子底物和产物的酶。
1）凝胶包埋法（网格型）
将酶或含酶菌体包埋在高分子凝胶细微网格中，制
成一定形状的固定化酶，称为网格型包埋法。也称
为凝胶包埋法。
首先被采用的网格包埋法是：
固定化胰蛋白酶 木瓜蛋白酶 －淀粉酶
在上述条件下，每10min增加0.001个消光值为 1个酶单位(U)(以下同)。
实验 木瓜蛋白酶的固定化
酶活力测定：
（2）残留酶活力测定：方法同溶液酶活力测定。
（3）固定化酶活力测定：取一块尼龙布固定化酶， 加入2.0mL激活剂，其余步骤与溶液酶测定相同。
生物化学英文课件-酶
immuno- characters.
Lactate dehydrogenase (LDH)
LDH
pyruvate Lactate
H subunit Tetramer LDH (M.W. 130,000)
M subunit Subunit: H (Chr12) M (Chr11)
Cellulose Acetate Membrane Electrophoresis result of LDH isoenzymes _
monomeric enzyme：only contain a
polypeptide chain with tertiary structure. oligomeric enzyme：contain two or more polypeptide chains associated by noncovalent bonds.
3.6 Clinical Applications of Enzymes
3.1 Structure and Function
of Enzymes
3.1.1 structure of enzymes
3.1.1.1 composition of Enzyme Molecules
Simple enzymes——proteins enzymes Conjugated enzymes (holoenzyme) apoenzyme
approximation and orientation of reactants
as bridge between substrate and enzyme
neutralize negative charges to decrease electrostatic repulsion
Enzyme酶
第一节 酶的分子结构与功能 一、酶的分子组成
酶分子可根据其化学组成的不同，分为两类： 单纯酶
酶→
酶蛋白
结合酶（全酶）→
辅酶
辅助因子→ 辅基
金属离子
由酶蛋白与辅助因子组成的酶称为全酶。
与酶蛋白疏松结合并与酶的催化活性有关 的耐热低分子有机化合物称为辅酶。
与酶蛋白牢固结合并与酶的催化活性有关 的耐热低分子有机化合物称为辅基。
催化反应历程
一般化学反应历程： S →P
酶促反应历程： S+E →
ES → E + P
（二）具有高度的底物特异性 l 一种酶只作用于一种或一类化合物，以促进一定的化 学变化，生成一定的产物，这种现象称为酶作用的特异 性。
一种酶只作用于一类化合物或一定的化学键，以促进一定的化学变化， 并生成一定的产物，这种现象称为酶的特异性或专一性(specificity)。 受酶催化的化合物称为该酶的底物或作用物(substrate)。
三、酶促反应的机制
（一）中间复合物学说
酶催化时，酶活性中心首先与底物结合生成一种 酶-底物复合物（ES），此复合物再分解释放出酶， 并生成产物。
S + E → SE → E + P
（二） 诱导契合学说
当底物与酶接近时，底物分子可以诱导酶活性中 心的构象发生改变，使之成为能与底物分子密切 结合的构象 。
丙二酸对琥珀酸脱氢酶的竞争性抑制
H2N-
-COOH对氨基苯甲酸
H2N-
-SO2NH对氨R 基苯磺酰胺
磺胺类药物对二氢叶酸合成酶的竞争性抑制
某些抑制剂的化学结构与底物相似，因而能与 底物竟争与酶活性中心结合。当抑制剂与活性 中心结合后，底物被排斥在反应中心之外，其 结果是酶促反应被抑制了。
5 Enzyme
Enzyme activity：Enzyme catalytic power generally can be
Specific activity of enzyme: purity of enzyme, generally expressed as U/mg protein. Turnover number（Kcat）：Measure of enzyme maximal
Projects/Titles for seminar
1. Research and applications of metalloenzymes
2. Progress in enzyme engineering
3. Artificial enzyme 4. Enzyme application
1. Enzyme generality
Chapter 5 Enzyme
1. Enzyme generality 2. Enzyme existing form
3. Mechanisms of enzyme action and
enzyme regulation 4. Enzyme kinetics 5. Enzyme engineering
(1) Oxidoreductases：EC1, involved in redox reactions, i.e., transfer of hydrogen or oxygen atoms between molecules. This class includes: dehydrogenases脱氢酶 (hydride transfer), oxidases (e- transfer to O2), oxygenase氧合酶 (oxygen atom transfer from O2), and peroxidases过氧化物酶 (e- transfer to peroxides) (2)Transferases：EC2, the transfer of an atom or group of atoms (like acyl-, alkyl- and glycosyl groups) between two molecules. The transferred groups are different from those transferred by the other classes of enzymes like Oxidoreductases, etc. (3)Hydrolases：EC3, catalyze hydrolytic reactions (and their reversals); this class includes esterases, glycosidases糖苷酶, proteases and lipases.
chapter5细胞通讯
Chapter 5 细胞通讯细胞通讯（Cell Communication）：细胞通讯是指在多细胞生物的细胞社会中, 细胞间或细胞内通过高度精确和高效地发送与接收信息的通讯机制, 并通过放大引起快速的细胞生理反应，或者引起基因活动,尔后发生一系列的细胞生理活动来协调各组织活动, 使之成为生命的统一整体对多变的外界环境作出综合反应。
P1675.1细胞通讯的基本特点5.1.1 细胞通讯的方式有三种通讯方式1.通过信号分子不依赖于细胞接触2.通过细胞与细胞的接触①通讯连接：间隙连接依赖于细胞接触胞间连丝②通过位于细胞表面的信号分子同靶细胞的接触。
3.通过细胞与细胞外基质粘着细胞通讯基本过程◆信号分子的合成内分泌细胞是主要来源◆信号分子的分泌复杂过程细胞信号传导◆信号分子的传递血液循环系统◆信号分子的识别受体蛋白◆信号转移跨膜转导信号转导◆信号转换细胞内级联反应◆信号解除细胞信号传导Cell signaling：强调信号的产生、分泌与传送, 即信号分子从合成的细胞中释放出来, 然后进行传递。
信号转导Signal transduction：强调信号的接收与接收后信号转换的方式(途径)和结果, 包括配体与受体结合、第二信使的产生及其后的级联反应等, 即信号的识别、转移与转换。
5.1.2信号分子Signal molecules1. 信号分子的概念（P169）化学物质：非营养物、非能源物质、非结构物质、不是酶主要是用来在细胞间和细胞内传递信息2. 信号分子的类型①激素：是由内分泌细胞合成的化学信号分子，通过血液循环运输到身体各个部位作用于靶细胞。
激素三种类型:蛋白与肽类激素脊椎动物中80％，只与质膜受体结合不溶于水，蛋白结合运输，胞内受体氨基酸衍生物激素酪氨酸衍生物两种受体②.局部化学介质：是由各种不同类型的细胞合成并分泌到细胞外液中的信号分子，它只能作用于周围的细胞。
常将这种信号传导称为旁分泌信号传导(paracrine signaling ）。
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Classification and nomenclature
The International Union of Biochemistry and Molecular Biology have developed a nomenclature for enzymes, the EC numbers; each enzyme is described by a sequence of four numbers preceded by "EC". The first number broadly classifies the enzyme based on its mechanism: The top-level classification is
and oxidation
EC 5 Isomerases: catalyze isomerization changes within a single
molecule
EC 6 Ligases: join two molecules with covalent bonds
The complete nomenclature can be browsed at /iubmb/enzyme/.
Relation of pH and enzyme activity pH-Activity Optimum of Several Enzyme
General properties
➢ effective; ➢ special; ➢can be regulated; ➢need serious conditions; ➢related to coenzyme, prosthetic and inorganic ions.
Catalysis
μ kat.L-1
Molar catalytic activity: that can be determinated when the pure enzyme with a known molecular weight is available. (μ kat.mol-1)
Factors Influencing Enzyme Reactions
Enzymes are positive catalysts. First, the enzyme must bind (noncovalently) a compound stereospecifically into the active site. Second, there must be chemical conversion of the initial compound into a new compound.
Effect of enzyme concentration on enzyme activity
Factors Influencing Enzyme Reactions (3) Effect of pH on Enzyme Activity
Each enzyme is catalytically active only in a narrow pH range and, as a rule, each has a pH optimum which is often between pH 5.5 and 7.5.
μ kat= μmol.S-1=10E-6kat 1 enzyme unit (U)≈1 μmol.min-1 (old denifinition)
Specific catalytic activity: the activity of the anzyme preparation in relation to the protein concentration.
Chapter Ⅴ
Enzymes
Key points
✓ Enzymatic Browning (酶促褐变) ✓ Enzymes used in food processing
Definition
Enzymes are proteins with catalytic activity due to their power of specific activation and conversion of substrates to products.
(1) Substrate Concentration on Enzyme Activity
Effect of cane sugar concentration on transferases activity
Factors Influencing Enzyme Reactions (2) Enzyme Concentration on Enzyme Activity
EC 1 Oxidoreductases: catalyze oxidation/reduction reactions EC 2 Transferases: transfer a functional group (e.g. a methyl or
phosphate group)
EC 3 Hydrolases: catalyze the hydrolysis of various bonds EC 4 Lyases: cleave various bonds by means other than hydrolysis
For example, a-chymotrypsin
"Lock and key" model Induced fit model
Enzymatic Activity
Enzyme activity is defined as the rate of substrate conversion or product formation under specific conditions, such as ce of cofactors and suitable temperature.