北京大学：《微生物学》课程PPT教学课件（英文版）The Purple Bacteria, also called

The bacteria Flavobacteria Deinococci Green sulfur and relatives bacteria Planctomyces and relative Green nonsulfur bacteria Chlamydiae Gram-positive bacteria thermotoga Aquifex /Hydrogenobacter Phylogenetic tree of the major lineages of Bacteria based on 16s ribosomaIrna Sequence comparisons

The Bacteria Phylogenetic tree of the major lineages of Bacteria based on 16S ribosomal RNA Sequence comparisons

The Purple bacteria, also called Proteobacteria is the largest and most physiological diverse of all bacteria Beta purple bacteria Chemolithotrophs lemoore Chemoorganotrophs Gamma purple Alpha purple bacteria bacteria Chemolithotrophs Chemoorganotrophs lithotrophs Epsilon purple bacteria (all chemoorganotrophs) Delta purple bacteria Phototroph (all chemoorganotrophs) Loss of photosynthetic ability Ancestral phototroph

The Purple Bacteria, also called Proteobacteria is the largest and most physiological diverse of all bacteria

Bacteria Purple and green(Anoxygenic Phototrophic Bacterial Cyanobacteria Prochlorophytes Chemolithotrophs: Nitrifying Bacteria Chemolithotrophs: Sulfur-and Iron-Oxidizing Bacteria Chemolithotrophs: Hydrogen-Oxidizing Bacteria Methanotrophs and methylotrophs Sulfate and sulfur-Reducing bacteria Homoacetogenic Bacteria Budding and appendaged (prosthecate) bacteria la Spirochetes Gliding bacteria Sheathed bacteria

Bacteria Purple and Green (Anoxygenic Phototrophic Bacteria) Cyanobacteria Prochlorophytes Chemolithotrophs: Nitrifying Bacteria Chemolithotrophs: Sulfur- and Iron-Oxidizing Bacteria Chemolithotrophs: Hydrogen-Oxidizing Bacteria Methanotrophs and Methylotrophs Sulfate and Sulfur-Reducing Bacteria Homoacetogenic Bacteria Budding and Appendaged (Prosthecate) Bacteria Spirilla Spirochetes Gliding Bacteria Sheathed Bacteria

Bacteria Pseudomonads Free-Living Aerobic Nitrogen-Fixing Bacteria Acetic Acid bacteria Zymomonas and Chromobacterium Vibrio and related genera Facultatively Aerobic Gram-Negative Rods Neisseria and other Gram-Negative Cocci Rickettsia Clamydias Gram-Positive bacteria: cocci Lactic Acid bacteria Endospore-Forming Gram-Positive Rods and Cocci Mycoplasmas High GC Gram-Positive Bacteria: " Actinomycetes Coryneform Bacteria Propionic Acid Bacteria Mycobacteria Filamentous Actinomycetes

Bacteria Pseudomonads Free-Living Aerobic Nitrogen-Fixing Bacteria Acetic Acid Bacteria Zymomonas and Chromobacterium Vibrio and Related Genera Facultatively Aerobic Gram-Negative Rods Neisseria and other Gram-Negative Cocci Rickettsias Clamydias Gram-Positive Bacteria: Cocci Lactic Acid Bacteria Endospore-Forming Gram-Positive Rods and Cocci Mycoplasmas High GC Gram-Positive Bacteria: “Actinomycetes” Coryneform Bacteria Propionic Acid Bacteria Mycobacteria Filamentous Actinomycetes

Facultatively Aerobic Gram-Negative Rods Enteric bacteria Gamma Purple bacteria Gram-negative straight rods Facultative aerobes Nonsporulating Motile by peritrichous flagella or nonmotile Large number of strains have been isolated Identification is now based on computer analysis of a large number of diagnostic tests carried out using miniaturized rapid diagnostic media kits and immunological and nucleic acid probes

Facultatively Aerobic Gram-Negative Rods Enteric Bacteria Gamma Purple bacteria Gram-negative straight rods Facultative aerobes Nonsporulating Motile by peritrichous flagella or nonmotile Large number of strains have been isolated Identification is now based on computer analysis of a large number of diagnostic tests carried out using miniaturized rapid diagnostic media kits and immunological and nucleic acid probes

Facultatively Aerobic Gram-Negative Rods H.C-C-cOo vate thMTPPH3C-C-TPP H C-C-Co0 ale acetolactate CH Butanediol-Producing, peritrichous Enteric Bacteria Erwinia carotovora, and its biochemical pathway for formation of butanediol from two CH, molecules of pyruvate H-C-OH 3-Butanediol

Facultatively Aerobic Gram-Negative Rods Butanediol-Producing, peritrichous Enteric Bacteria Erwinia carotovora, and its biochemical pathway for formation of butanediol from two molecules of pyruvate

(a)Mixed acid fermentation(for example, Escherichia coll) Typical products(molar amounts) Glucose yruvate 一 Lactate Acidic. neutral 4:1 cO c2:H2 1:1 Succinate Ethanol Acetyl-CoA Fermentation products Acetate are the key to separate cO2 the enteric bacteria Formate (b) Butanediol fermentation (for example, Enterobacter Typical products(molar amounts 2.3-Butanediol+ co idic. neutra 1:6 Ethanol cO2: H2 5:1 Lactate Glucose pyruvate Succinate Acetate CO2+ H2

Fermentation products are the key to separate the enteric bacteria

Two Broad Patterns of Fermentations Mixed-Acid Fermenters: Butanediol Producers Proteus Klebsiella Citrobacter Enterobacter Edwardsiella Serratia Salmonella Erwinia Escherichia Hafnia shigella

Two Broad Patterns of Fermentations Mixed-Acid Fermenters: Proteus Citrobacter Edwardsiella Salmonella Escherichia Shigella Butanediol Producers Klebsiella Enterobacter Serratia Erwinia Hafnia

Diagnostic test Go to number 1 MR + VP Facultatively (mixed-acid fermenters) MR VP+ Aerobic gram (butanediol producers) 2 Urease 27P346 Proteus Negative Rods Urease 3 H2s (Si+ H2s (si) A simplified key to identify 4 KCN+ KCN Citrobacter the main genera of enteric 5 5 Indole + citrate Edwardsiella bacteria Indole-: citrate+ Salmonella 6 Gas from glucose Escherichia No gas from glucose Shigella 7 Nonmotile: ornithine Klebsiella Motile: ornithine+ 8 8 Gelatin + DNAse Serratia (red pigment Gelatin slow: DNAse Enterobacter K Mixed-acid fermenters Butanediol producers

Facultatively Aerobic Gram￾Negative Rods A simplified key to identify the main genera of enteric bacteria

Escherichia Universal in habitants of the intestinal tract Play nutritional role(synthesizing vitamins) Consume O2, render the large intestine anoxic Some are pathogenic Diarrhea Children’ s nurseries Urinary infections Enterotoxin

Escherichia Universal inhabitants of the intestinal tract Play nutritional role (synthesizing vitamins) Consume O2, render the large intestine anoxic Some are pathogenic Diarrhea Children’s nurseries Urinary infections Enterotoxin