华中农业大学微生物英文版课件3
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华中农业大学微生物英文版课件9
9.1 Microorganisms in nature ecosystem
1. Microorganisms and microenvironment 2. Terrestrial Environments 3. Freshwater Environments 4. Marine Environments
Metabolically related populations constitute groupings called guilds.
Sets of guilds conducting complementary physiological processes interact to form microbial communities.
9.2 Microbial population interactions
1， neutralism (中性关系 ) 2， commensalism (偏利关系 ) 3， synergism (协同关系 ) 4， mutualism (互惠关系 ) 5， competition (竞争关系 ) 6， antagonism (拮 抗关系 ) 7， parasitism (寄生关系 ) 8， predation (捕食关系 )
Numbers / g
Biomass (g / m3）
Bacteria
108
160
Fungi
105
200
Actinomycetes
105 - 106
160
Algae
104 - 105
32
Protozoa
104
38
Main types of soil microorganisms
Agrobacterium Arthrobacter Caulobacter Clostridium Flavobacterium Mycobacterium Staphylcoccus
微生物学英文课件
HyServe
Compact Dry SL (Salmonella)
• Salmonella form green colonies/aereas and change the medium to yellow
-> Salmonella decarboxylase alkalizes the medium and changes the medium from purple to yellow
3M Petrifilm • flexible film -> not stackable
-> elaborate closing procedure
-> 3-dimensional growth impos • different technology -> squeezer causes problems with air bubbles
HyServe
Benefits compared to the 3M Petrifilm concept
Compact Dry • solid cartridge -> unlimited stackable -> safe, closed cover -> 3-dimensional growth of molds • similar to petridish -> higher acceptance for conventional microbiology customer -> colony picking is possible
-> risk of contamination during inoculation procedure
HyServe
微生物生长 华中农业大学微生物学课件
3、薄膜过滤计数法
用于计 数空气 或水中 的含菌
数
菌数低样品（如水）→膜过滤→培养→菌落计数
（二）细胞生物量的测定
n 测定细胞干重法
单位体积培养物中细胞物质的干重
n 含氮量测定法
微生物细胞中蛋白质的含量是比较稳定的，测出微生物 细胞中的含N量后再换算出蛋白质的含量，可用凯氏定 N法 。
蛋白质的含量=氮量×6.25
2. 利用选择性培养基分离
微生物群落中数量占少数的微生物的分离纯化
t 抑制大多数其它微生物的生长
t 使待分离的微生物生长更快
使待分离的微生物在群落中的数量 上升，方便用稀释法对其进行纯化。
根据所要分离的菌种特性选用培养基，如：
不同菌对营养的要求
分离真菌，用马丁氏培养基，pH偏酸 分离放线菌，用高氏1号，pH中性偏碱
Chapter 6 第六章 微生物的生长与环境条件
n 第一节 微生物生长量的测定 n 第二节 细菌群体的生长 n 第三节 环境条件对微生物生长和代谢的影响
第一节 微生物生长量的测定
一. 获得纯培养的方法 二. 细菌群体生长的测定
一、获得纯培养的方法
q 微生物在自然界总是混杂地生活，要 想研究某一种微生物，必须把研究对象 从混杂群体中分离出来。
2、最大概率法 (MPN 法)
§ 将待测菌液作十倍系列稀释，每稀释度3—5个重复，培养后 检查细菌的生长，以有细菌生长的最后三个稀释度的管数作数 量指标，由数理统计表查出近似值，再乘以数量指标第一位的 稀释倍数，即为原菌液的菌数。
例如：某细菌在稀释培养法中生长情况如下：
稀释度：
10—3，10—4，10—5，10—6，10—7，10—8
§ 稀释分离
华中农业微生物学第一章英文版
• The development of microbiology as a scientific discipline has depended on the availability of the microscope and the ability to isolate and grow pure cultures of microorganisms.
of microbiology
Concepts
• Microorganisms are responsible for many of the changes observed in organic and inorganic matter (e.g., fermentation and the carbon, nitrogen and sulfur cycles that occurred in nature.
The first person to accurately observe and describe microorganisms
The first person to observe and describe microorganisms was the amateur microscopist Antony van leeuwenhoek of Delft, Holland.
lens
Object being viewed
adjusting screws
A drawing of one of the microscopes showing the lens a; mounting pin b; and focusing screws c and d.
• Microbiology is a large discipline, which has a great impact on other areas of biology and general human welfare
of microbiology
Concepts
• Microorganisms are responsible for many of the changes observed in organic and inorganic matter (e.g., fermentation and the carbon, nitrogen and sulfur cycles that occurred in nature.
The first person to accurately observe and describe microorganisms
The first person to observe and describe microorganisms was the amateur microscopist Antony van leeuwenhoek of Delft, Holland.
lens
Object being viewed
adjusting screws
A drawing of one of the microscopes showing the lens a; mounting pin b; and focusing screws c and d.
• Microbiology is a large discipline, which has a great impact on other areas of biology and general human welfare
华中农业大学微生物英文版课件9
Rhizosphere Effect ( R/S ratio )
The rhizosphere is the soil region in close contact with plant roots.
Within the rhizosphere, the plant roots exert a direct influence on the soil bacteria. This influence is known as the rhizosphere effect.
Community 3
Microbial communities then interact with communities of macroorganisms to define the entire ecosystem.
The distribution of microorganisms in nature ecosystem depends on the resources (nutrients) available and on the growth conditions. Temperature, pH, water availability, light, oxygen of a habitat define the niche for each particular microorganism.
9.1.2. Terrestrial Environments
Proportion of different soil microorganisms in soil
Microbial number and biomass in cultivated field soil（15 cm）
Microbes Bacteria Fungi
华中农业大学微生物英文版课件
Huazhong Agricultural University Microbiology Engl
目录
CONTENTS
• Introduction • Types of Microorganisms • Microbial Metabolism • Microbial Life Processes • Microbial Ecology • Microbial Pathogenesis and Disease
04 Microbial Life Processes
Cell Structure and Function
Cell membrane
Composition, function, and transport processes across the membrane
Cell wall
Structure, function, and role in maintaining cell shape and protecting the cell
Fungi play important roles in composition, nutrient cycling, and symbolic relationships with plants and animals
Some fungi are editable and have culinary uses, while others can cause diseases in plants and animals
Cultivation and Respiration
Microorganisms can be cultured in different environments, such as on solid surfaces or in liquid media The choice of cultivation environment depends on the type of microbiology and the desired outcome of the experience or study
目录
CONTENTS
• Introduction • Types of Microorganisms • Microbial Metabolism • Microbial Life Processes • Microbial Ecology • Microbial Pathogenesis and Disease
04 Microbial Life Processes
Cell Structure and Function
Cell membrane
Composition, function, and transport processes across the membrane
Cell wall
Structure, function, and role in maintaining cell shape and protecting the cell
Fungi play important roles in composition, nutrient cycling, and symbolic relationships with plants and animals
Some fungi are editable and have culinary uses, while others can cause diseases in plants and animals
Cultivation and Respiration
Microorganisms can be cultured in different environments, such as on solid surfaces or in liquid media The choice of cultivation environment depends on the type of microbiology and the desired outcome of the experience or study
华中农业大学微生物英文
extracellular and intracellular
Virion, the extracellular phase, posses Байду номын сангаасew if any enzymes and can not reproduce independently of living cells. In the intracellular phase, viruses exist primarily as replicating nucleic acids that induce host metabolism to synthesize virion components; eventually complete virus particles or virions are released.
Size
Viruses vary considerably in size. Although most are quite a bit smaller than bacteria, some of the larger viruses (such as the smallpox virus) are about the same size as some very small bacteria (such as the mycoplasmas, rickettsias, and chlamydias).
Chapter 5 Viruses
Chapter outline
5.1 General Properties of Viruses 5.2 General Features of Virus Reproduction 5.3 Overview of Bacterial Viruses 5.4 Temperate Bacteriophages: Lysogeny and Lambda 5.5 Overview of Animal Viruses 5.6 Pox Viruses 5.7 Adcnoviruses 5.8 Retroviruses 5.9 Viroids and Prions
Virion, the extracellular phase, posses Байду номын сангаасew if any enzymes and can not reproduce independently of living cells. In the intracellular phase, viruses exist primarily as replicating nucleic acids that induce host metabolism to synthesize virion components; eventually complete virus particles or virions are released.
Size
Viruses vary considerably in size. Although most are quite a bit smaller than bacteria, some of the larger viruses (such as the smallpox virus) are about the same size as some very small bacteria (such as the mycoplasmas, rickettsias, and chlamydias).
Chapter 5 Viruses
Chapter outline
5.1 General Properties of Viruses 5.2 General Features of Virus Reproduction 5.3 Overview of Bacterial Viruses 5.4 Temperate Bacteriophages: Lysogeny and Lambda 5.5 Overview of Animal Viruses 5.6 Pox Viruses 5.7 Adcnoviruses 5.8 Retroviruses 5.9 Viroids and Prions
华中农业大学微生物学
Gram-positive Cell Wall
The Gram-positive cell wall has a peptidoglycan layer that is relatively thick (ca. 40 nm) and comprises approximately 90% of the cell wall. The cell walls of most Gram-positive eubacteria also have teichoic acids.
Naked eye
Eukaryotes
Light microscope
Electron microscope
Prokaryotes Viruses
Surface area and volume relationships in cells
a cell increases in size, its surface area – to – volume ratio decreases
Chemical Structure of Lipopolysaccharide
O side chain
Core polysaccharide
Lipid A
Molecular Model of E.coli Lipopolysaccharide
Cell Walls of Archaebacteria
The Prokaryotic Cell
1. Their genetic material (DNA) is not enclosed within a membrane and they lack other membrane – bounded organelles
(优选)华中农业微生物学第一章英文版ppt讲解
• The development of microbiology as a scientific discipline has depended on the availability of the microscope and the ability to isolate and grow pure cultures of microorganisms.
Our world is populated by invisible creatures too small to be seen with the unaided eye. These life forms, the microbes or microorganisms, may be seen only by magnifying their image with a microscope.
of microbiology
Concepts
• Microorganisms are responsible for many of the changes observed in organic and inorganic matter (e.g., fermentation and the carbon, nitrogen and sulfur cycles that occurred in nature.
Fungi (unicellular or multicellular)
Protozoa (unicellular)
Other (multicellular organisms)
The size and cell type of microbes
Most of the bacteria, protozoa, and fungi are single-celled microorganisms, and even the multicelled microbes do not have a great range of cell types. Viruses are not even cells, just genetic material surrounded by a protein coat and incapable of independent existence.
Our world is populated by invisible creatures too small to be seen with the unaided eye. These life forms, the microbes or microorganisms, may be seen only by magnifying their image with a microscope.
of microbiology
Concepts
• Microorganisms are responsible for many of the changes observed in organic and inorganic matter (e.g., fermentation and the carbon, nitrogen and sulfur cycles that occurred in nature.
Fungi (unicellular or multicellular)
Protozoa (unicellular)
Other (multicellular organisms)
The size and cell type of microbes
Most of the bacteria, protozoa, and fungi are single-celled microorganisms, and even the multicelled microbes do not have a great range of cell types. Viruses are not even cells, just genetic material surrounded by a protein coat and incapable of independent existence.
微生物英文课件-eucaryotes
• Rough endoplasmic reticulum (RER)– originates from the outer membrane of the nuclear envelop & extends in a continuous network through cytoplasm; rough due to ribosomes, proteins are synthesized & shunted into the ER for packaging & transport. First step in secretory pathway.
)
4.2.4. The cell membrane
- typical bilayer of phospholipids and proteins
- Sterols (固醇) confer stability - serve as selectively permeable barriers in transport; involved in cell-cell recognition, endo- and exocytosis and adhesion to surface; transport system is located in membrane
-Eukaryotic cells also contain membrane-bound organelles that account for 60-80% of their volume
•The most obvious difference between Eukaryotic cells and procaryotic cells is in their use of membranes.
微生物学英文课件-Viruses
# 1 Microbiology Unit 3 -Bacterial Genetics and VirusesPart 3: Viruses•Viruses -non-living infectious agents that may infect all living things.•Commonly named according to which host is infected.•Terms–Virion: virus particle consisting of protein coat/nucleicacid.–Capsid: term for viral protein coat–Capsomere: identical protein subunits of the capsid–Nucleocapsid: Viral capsid along with tightly packednucleic acid.–Envelope: Double layer of lipid surrounding the capsid.Microbiology Unit 3 -Bacterial Genetics and Viruses# 1Part 3: VirusesMicrobiology Unit 3 -Bacterial Genetics and Viruses# 1Part 3: VirusesMicrobiology Unit 3 -Bacterial Genetics and VirusesPart 3: VirusesShape and Classification of RNA Viruses# 2 Shape and Classification of RNA Viruses# 2Shape and Classification of DNA Viruses # 2Relative Size of Viruses •Viruses 100-1000X smallerthan hosts: 10-500 nm.•Attachment via–Spikes (attachment proteinsproject from tailless capsid)–Tails (tail fibers used )–Not needed for plant viruses•Viral genome may be–Single or double stranded,DNA or RNA–DNA may be circular or linear–Very small genome.# 3/4/5Requirement for Viruses To Grow Inside Living Cells •Must have actively multiplying host cell for viral replication.•Viruses lack enzymes to make either enzymes or proteins.•Necessary to use host enzymes and cell structures for viral reproduction.•Two phases of viruses –Outside living cells: viruses are inert macromolecules –Inside living cells: viruses redirect host metabolism for viral reproduction.•Necessary Genetic Information Needed by Viruses –Viral protein coat –Replication for Viral nucleic acid–Movement of virus in and out of host.# 6# 7 Outcomes of Viral Infection of Bacteria1) Virulent or lytic phage, e.g.,T4–Redirect cell to make more phage and lyse the cell.2) Non-lytic phage, e.g.,filamentous phage -M13–Partial takover of cell metabolism to make more phagethen leak out into environment without killing cell.3) Temperate phage, e.g. Lambda (λ) phage–Produce “latent “ infections as they are incorporated intobacterial genome.–Replicate along with the host–Produce “lysogenic conversion” -coding for proteinsdifferent than those native to the host, e.g., C. diphtheriae Outcomes of Phage Infection of Bacteria# 7Bacterial Infection with Virulent TLytic Phage# 84Bacterial Infection with Temperate λ Phage# 9Transduction Review# 10•Bacterial gene transfer via bacteriophage.•General vs. specialized.–General: Any gene of the donor cell is transferred–Specialized:•Only selected genes from donor cell are transferred.•Only temperate phages are involved in transduction•Phage integrates at certain sites into the bacterialchromosome.•Examples are Lambda phage in E. coli and toxinproduction in Corynebacterium diphtheriaeGene Transfer in Bacteria -Transduction# 10Specialized Transduction Via Temperate Phage# 10 Virulent Properties Conferred to Bacterial HostsVia ProphageHost Ranges of Bacteriophage# 11•Host range of phage limited to specific bacterial species and often to only a few strains.•Important limitation factors:–Phage needs specific receptor sites on host cell surface•Receptor sites may be altered via mutation or lysogenic conversion.–Restriction modification system on host cell must be overcome •Host bacteria have 2 adjacent genes–Restriction enzyme–Modification enzyme.•Because of limited host range, DNA rarely transferred between species.。
临床微生物真菌学英文课件PPT讲义精
The diagnosis of skin infections is usually based on clinical manifestations and laboratory tests, and treatment mainly includes local medication and oral medication.
Microorganisms can be multiple by binary session, padding, or other methods, depending on the specifications
Pathogenesis
Coexistence and competition
Diagnosis: Identification of the causative agent of a disease is critical for accurate diagnosis and treatment Microbiological tests can identify the presence of microorganisms in clinical samples, such as blood, urine, and issue biopsy specifications
Enzyme lay (ELISA)
A technique that uses antibiotics linked to an enzyme to detect microbial antibodies in serum or other body fluids It is widely used in clinical microbiology and mycology for the diagnosis of various infections
Microorganisms can be multiple by binary session, padding, or other methods, depending on the specifications
Pathogenesis
Coexistence and competition
Diagnosis: Identification of the causative agent of a disease is critical for accurate diagnosis and treatment Microbiological tests can identify the presence of microorganisms in clinical samples, such as blood, urine, and issue biopsy specifications
Enzyme lay (ELISA)
A technique that uses antibiotics linked to an enzyme to detect microbial antibodies in serum or other body fluids It is widely used in clinical microbiology and mycology for the diagnosis of various infections
微生物学【英文版】(全套课件499P)
Concepts
Microorganisms are responsible for many of the changes observed in organic and inorganic matter (e.g., fermentation and the carbon, nitrogen and sulfur cycles that occurred in nature.
Microbiology is a large discipline, which has a
1.1 What is a microbe?
The word microbe (microorganism) is used to describe an organism that is so small that can not be seen without the use of a microscope. Viruses, bacteria, fungi, protozoa and some algae are all included in this category.
Microbial world
Organisms
(living)
Infectious agents (non-living) viruses viroids prions
Prokaryotes (unicellular)
eukaryotes
Eubacteria
Archaea
Algae (unicellular or multicellular)
Chapter 1
Microorganisms and Microbiology
pter outline
1.1 What is a microbe? 1.2 The importance of Microbiology 1.3 Microbes in our lives 1.4 The history of microbiology 1.5 Important events in the development of microbiology
微生物英文课件-procaryotes-A
Chemotaxis (趨化性):chemo, chemical; taxis, an ordering or arrangement
1. Stab the cell into semisolid medium in a test tube
2. Observe the cell under the microscope with a hanging drop slide
Flagellar structure
(Brock, P75)
Filament 鞭毛絲 --
long, thin, helical structure composed of proteins
Hook 鉤形鞘-- curved sheath
Basal body 基體-- stack of rings firmly anchored
Peptidoglycan structure
(Brock, P60)
• Back bone: repeating disaccharides of NAM and NAG
• Tetrapeptide (4 alternating D- and L- aa): attached to NAM
• Peptide cross link:
Structure of the cell wall
gram-positive
gram-negative cell
The cell wall helps determine the shape of a bacterium, provides the kind of strong structural support necessary to keep a bacterium from bursting or collapsing because of changes in osmotic pressure
1. Stab the cell into semisolid medium in a test tube
2. Observe the cell under the microscope with a hanging drop slide
Flagellar structure
(Brock, P75)
Filament 鞭毛絲 --
long, thin, helical structure composed of proteins
Hook 鉤形鞘-- curved sheath
Basal body 基體-- stack of rings firmly anchored
Peptidoglycan structure
(Brock, P60)
• Back bone: repeating disaccharides of NAM and NAG
• Tetrapeptide (4 alternating D- and L- aa): attached to NAM
• Peptide cross link:
Structure of the cell wall
gram-positive
gram-negative cell
The cell wall helps determine the shape of a bacterium, provides the kind of strong structural support necessary to keep a bacterium from bursting or collapsing because of changes in osmotic pressure
Chapter 3 The Prokaryotes 微生物学 教学课件 英文版
3.2 Actinomycetes
Actinomycetes are filamentous bacteria. Their morphology resembles that of the filamentous fungi; however, the filaments of actinomycetes consist of procaryotic cells. Some actinomycetes resemble molds by forming externally carried asexual spores for reproduction.
Chain of conidiospores
Aerial hyphae
Agar surface
Substrate mycelium
The cross section of an actinomycete colony showing the substrate mycelium and aerial mycelium with chains of conidiospores
Rod-shaped bacteria
Bacilli divide only across their short axis, so there are fewer groupings of bacilli than of cocci.
Single bacillus
Diplobacilli
streptobacilli
Some bacteria are shaped like long rods twisted into spirals or helices; they are called vibrios (like commas or incomplete spirals), spirilla if rigid and spirochetes when flexable.
最新华中农业大学微生物英文版课件3
______________________________ ____________________
______________________________ ____________________
How to identify an unknown bacterial species ?
Chaper 3 The Prokaryotes
Section 1 Section 2 Section 3 Section 4 Section 5
Bacteria Actinomycetes Cyanobacteria Archaeobacteria Other prokaryotes
______________________________ ____________________
______________________________ ____________________
Байду номын сангаас
Rod-shaped bacteria
Bacilli divide only across their short axis, so there are fewer groupings of bacilli than of cocci.
They have a few basic shapes-spherical coccus (plural, cocci, meaning berries), rod-shaped bacillus (plural, bacilli, meaning little staffs), and spiral.
Spherical coccus
The Micrococcaceae
The family Micrococcaceae contains gram-positive cocci, 0.5-2.5 μm in diameter, that divide in more than one plane to form regular or irregular clusters of cells. All are aerobic or facultatively anaerobic. The peptidoglycan di-amino acid is L-lysine.
______________________________ ____________________
How to identify an unknown bacterial species ?
Chaper 3 The Prokaryotes
Section 1 Section 2 Section 3 Section 4 Section 5
Bacteria Actinomycetes Cyanobacteria Archaeobacteria Other prokaryotes
______________________________ ____________________
______________________________ ____________________
Байду номын сангаас
Rod-shaped bacteria
Bacilli divide only across their short axis, so there are fewer groupings of bacilli than of cocci.
They have a few basic shapes-spherical coccus (plural, cocci, meaning berries), rod-shaped bacillus (plural, bacilli, meaning little staffs), and spiral.
Spherical coccus
The Micrococcaceae
The family Micrococcaceae contains gram-positive cocci, 0.5-2.5 μm in diameter, that divide in more than one plane to form regular or irregular clusters of cells. All are aerobic or facultatively anaerobic. The peptidoglycan di-amino acid is L-lysine.
演示文稿华中农业微生物学第一章英文(共40页)
第十一页，共四十页。
The disease-causing ability of some microbes is well known. However, microorganisms have also provided us with the means of their control in the form of antibiotics and other medically important drugs.
（优选）华中农业微生物学第 一章英文版ppt讲解
第一页，共四十页。
Chapter outline
1.1 What is a microbe? 1.2 The importance of Microbiology 1.3 Microbes in our lives 1.4 The history of microbiology
The environment
Medicine
Food
Biotechnology
Research
第九页，共四十页。
• The environment • Medicine
• Food
• Biotechnology
• Research
Press here to continue
第十页，共四十页。
Microbes are responsible for the geochemical cycles. They are found in association with plants in symbiotic relationships. Some microbes are devastating plant pathogens, but others may act as biological control agents against diseases.
The disease-causing ability of some microbes is well known. However, microorganisms have also provided us with the means of their control in the form of antibiotics and other medically important drugs.
（优选）华中农业微生物学第 一章英文版ppt讲解
第一页，共四十页。
Chapter outline
1.1 What is a microbe? 1.2 The importance of Microbiology 1.3 Microbes in our lives 1.4 The history of microbiology
The environment
Medicine
Food
Biotechnology
Research
第九页，共四十页。
• The environment • Medicine
• Food
• Biotechnology
• Research
Press here to continue
第十页，共四十页。
Microbes are responsible for the geochemical cycles. They are found in association with plants in symbiotic relationships. Some microbes are devastating plant pathogens, but others may act as biological control agents against diseases.
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Chaper 3
The Prokaryotes
Bacteria Actinomycetes Cyanobacteria Archaeobacteria Other prokaryotes
Section 1 Section 2 Section 3 Section 4 Section 5
Bacteria
Antibiotics
Over 500 distinct antibiotic substances have been shown to be produced by streptomycete.
Most antibiotics are efficient against different bacteria. More than 50 antibiotics have been used in human and veterinary medicine, agriculture and industry
The method of a serial dilutions for viable counting
Concept:
• The streptonycetes are a large group of filamentous, gram positive bacteria that form spores at the end of aerial filaments. • They have the highest GC percentagein the DNA base composition of any bacteria known.
Arrangement of Spherical Bacterial Cells
diplococci
sarcinae
streptococci staphylococci
tetracocci
Spherical coccus
The Micrococcaceae
The family Micrococcaceae contains gram-positive cocci, 0.5-2.5 μm in diameter, that divide in more than one plane to form regular or irregular clusters of cells. All are aerobic or facultatively anaerobic. The peptidoglycan di-amino acid is L-lysine. The three most important genera are: Micrococcus Staphylococcus Streptococcus
Rod-shaped
bacteria
Bacilli divide only across their short axis, so there are fewer groupings of bacilli than of cocci.
Single bacillus Diplobacilli streptobacilli
spirillum
spirochete
Actinomycetes
Actinomycetes are filamentous bacteria. Their morphology resembles that of the filamentous fungi; however, the filaments of actinomycetes consist of procaryotic cells. Some actinomycetes resemble molds by forming externally carried asexual spores for reproduction.
How to identify an unknown bacterial species ? The thousands of species of bacteria are differentiated by many factors, including morphology (shape), chemical composition (often detected by staining reactions), nutritional requirements, biochemical activities, and source of energy (sunlight or chemicals).
Size, Shape, and Arrangement of Bacterial Cells Most bacteria fall within a range
Cm = 10-2 meter mm = 10-3 meter μm = 10-6 meterm 0.2 to 2.0 μm in diameter
The cross section of an actinomycete colony showing the substrate mycelium and aerial mycelium with chains of conidiospores
Chain of conidiospores
Aerial hyphae
Staphylococcus - facultatively anaerobic, grampositive, usually form irregular clusters, nonmotile, catalase positive but oxidase negative, ferment glucose anaerobically.
Pseudomonas
Rhizobium
Azotobacter
Vibrio, Spirillum and Spirochete
vibrio Some bacteria are shaped like long rods twisted into spirals or helices; they are called vibrios (like commas or incomplete spirals), spirilla if rigid and spirochetes when flexable.
Coccobacillus
Spore-forming rod shaped bacteria
Almost all Spore-forming bacteria are Gram+
Bacillus – Aerobic Bacillus subtilis, B. Mycoides B. Pastturii B. megaterium B. Thuringiensis B. Anthracis B. Botulinus B. cereus
Clostridium – Anaerobic
Clostridium botulinus C. butyricum C. aceticum C. tetani C. putrificum
Nonspore - forming rod shaped bacteria
Most nonspore – forming rod shaped bacteria are GramRepresentatives: Escherchia coli Alcaligenes Proteus Flavobacteria
• Streptomyces require a lower water potential for growth than many other soil bacteria.
• Media often selective for Streptomyces contain the usual assortment of inorganic salts
Agar surface
Substrate mycelium
Streptomyces spores, called conidia, are not related in any way to the endospores of Bacillus and Clostridium because the streptomycete spores are produced simply by the formation of crosswalls in the multinucleate sporophores followed by separation of the individual cells directly into spores.
The cross section of an actinomycete colony showing the substrate mycelium and aerial mycelium with chains of conidiospores
Actinomycetes Representive genera: Streptomyces Nocardia Actinomyces Micromonospora Streptosporangium Actinoplanes Frankia
and from 2 to 8μm in length.
They have a few basic shapes-spherical coccus (plural, cocci, meaning berries), rod-shaped bacillus (plural, bacilli, meaning little staffs), and spiral.
• Many clinically important antibiotics have come from Streptomycetes species
Cyanobacteria
The cyanobacteria have typical prokaryotic cell structures and a normal gram-negative cell wall.
The Prokaryotes
Bacteria Actinomycetes Cyanobacteria Archaeobacteria Other prokaryotes
Section 1 Section 2 Section 3 Section 4 Section 5
Bacteria
Antibiotics
Over 500 distinct antibiotic substances have been shown to be produced by streptomycete.
Most antibiotics are efficient against different bacteria. More than 50 antibiotics have been used in human and veterinary medicine, agriculture and industry
The method of a serial dilutions for viable counting
Concept:
• The streptonycetes are a large group of filamentous, gram positive bacteria that form spores at the end of aerial filaments. • They have the highest GC percentagein the DNA base composition of any bacteria known.
Arrangement of Spherical Bacterial Cells
diplococci
sarcinae
streptococci staphylococci
tetracocci
Spherical coccus
The Micrococcaceae
The family Micrococcaceae contains gram-positive cocci, 0.5-2.5 μm in diameter, that divide in more than one plane to form regular or irregular clusters of cells. All are aerobic or facultatively anaerobic. The peptidoglycan di-amino acid is L-lysine. The three most important genera are: Micrococcus Staphylococcus Streptococcus
Rod-shaped
bacteria
Bacilli divide only across their short axis, so there are fewer groupings of bacilli than of cocci.
Single bacillus Diplobacilli streptobacilli
spirillum
spirochete
Actinomycetes
Actinomycetes are filamentous bacteria. Their morphology resembles that of the filamentous fungi; however, the filaments of actinomycetes consist of procaryotic cells. Some actinomycetes resemble molds by forming externally carried asexual spores for reproduction.
How to identify an unknown bacterial species ? The thousands of species of bacteria are differentiated by many factors, including morphology (shape), chemical composition (often detected by staining reactions), nutritional requirements, biochemical activities, and source of energy (sunlight or chemicals).
Size, Shape, and Arrangement of Bacterial Cells Most bacteria fall within a range
Cm = 10-2 meter mm = 10-3 meter μm = 10-6 meterm 0.2 to 2.0 μm in diameter
The cross section of an actinomycete colony showing the substrate mycelium and aerial mycelium with chains of conidiospores
Chain of conidiospores
Aerial hyphae
Staphylococcus - facultatively anaerobic, grampositive, usually form irregular clusters, nonmotile, catalase positive but oxidase negative, ferment glucose anaerobically.
Pseudomonas
Rhizobium
Azotobacter
Vibrio, Spirillum and Spirochete
vibrio Some bacteria are shaped like long rods twisted into spirals or helices; they are called vibrios (like commas or incomplete spirals), spirilla if rigid and spirochetes when flexable.
Coccobacillus
Spore-forming rod shaped bacteria
Almost all Spore-forming bacteria are Gram+
Bacillus – Aerobic Bacillus subtilis, B. Mycoides B. Pastturii B. megaterium B. Thuringiensis B. Anthracis B. Botulinus B. cereus
Clostridium – Anaerobic
Clostridium botulinus C. butyricum C. aceticum C. tetani C. putrificum
Nonspore - forming rod shaped bacteria
Most nonspore – forming rod shaped bacteria are GramRepresentatives: Escherchia coli Alcaligenes Proteus Flavobacteria
• Streptomyces require a lower water potential for growth than many other soil bacteria.
• Media often selective for Streptomyces contain the usual assortment of inorganic salts
Agar surface
Substrate mycelium
Streptomyces spores, called conidia, are not related in any way to the endospores of Bacillus and Clostridium because the streptomycete spores are produced simply by the formation of crosswalls in the multinucleate sporophores followed by separation of the individual cells directly into spores.
The cross section of an actinomycete colony showing the substrate mycelium and aerial mycelium with chains of conidiospores
Actinomycetes Representive genera: Streptomyces Nocardia Actinomyces Micromonospora Streptosporangium Actinoplanes Frankia
and from 2 to 8μm in length.
They have a few basic shapes-spherical coccus (plural, cocci, meaning berries), rod-shaped bacillus (plural, bacilli, meaning little staffs), and spiral.
• Many clinically important antibiotics have come from Streptomycetes species
Cyanobacteria
The cyanobacteria have typical prokaryotic cell structures and a normal gram-negative cell wall.