北京大学：《微生物学》课程PPT教学课件（英文版）The Bacteria

The bacteria Dirochetes 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 Filamentoud 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 Filamentoud Actinomycetes

Sulfate- and Sulfur-Reducing Bacteria Representative Sulfate-reducing and sulfur-reducing bacteria Most are Delta Purple bacteria Desulfosarcina variabilis Desulfovibrio desulfuricans h Desulfobacterpostgatei ) 入S裂 Desulfonema limicola Desulfobulbus propionicus Sulfur-reducing bacteria 0 Desulfuromonas acetoxidans

Sulfate- and Sulfur-Reducing Bacteria Representative Sulfate-reducing and sulfur-reducing bacteria Most are Delta Purple Bacteria Desulfovibrio desulfuricans Desulfonema limicola Desulfobacter postgatei Desulfobulbus propionicus Desulfosarcina variabilis Desulfuromonas acetoxidans Sulfur-reducing bacteria

Sulfate-Reducing bacteria Strict anaerobes, Divided into two broad physiological subgroups: Genera in Group I(Desulfovibrio, Desulfomonas Desulfotomaculum, Desulfobulbus utilize lactate, pyruvate, ethanol, or certain fatty acids as carbon and energy sources, reducing sulfate to hydrogen sulfide Genera in Group I (Desulfococcus, Desulfosarcina Desulfonema, Desulfonema) specialize in the oxidation of fatty acids, particularly acetate, reducing sulfate to sulfide Growth and reduction of sulfate by Desulfotomaculum in certain canned foods leads to a type of spoilage called sulfide stinker, Habitants of anoxic aquatic and terrestrial environments

Sulfate-Reducing Bacteria Strict anaerobes, Divided into two broad physiological subgroups: Genera in Group I (Desulfovibrio, Desulfomonas, Desulfotomaculum, Desulfobulbus) • utilize lactate, pyruvate, ethanol, or certain fatty acids as carbon and energy sources, reducing sulfate to hydrogen sulfide Genera in Group II (Desulfococcus, Desulfosarcina, Desulfonema, Desulfonema) • specialize in the oxidation of fatty acids, particularly acetate, reducing sulfate to sulfide Growth and reduction of sulfate by Desulfotomaculum in certain canned foods leads to a type of spoilage called sulfide stinker, Habitants of anoxic aquatic and terrestrial environments

Sulfur-Reducing bacteria Able to reduce elemental sulfur to sulfide Unable to reduce sulfate to sulfide Obligate anaerobes Utilize only sulfur as an electron acceptor Also referred to as dissimilatory sulfur reducing bacteria Members of the genus Desulfuromonas can grow anaerobically by coupling the oxidation of substrates such as acetate to ethanol to the reduction of elemental sulfur to hydrogen sulfide

Sulfur-Reducing Bacteria Able to reduce elemental sulfur to sulfide Unable to reduce sulfate to sulfide Obligate anaerobes Utilize only sulfur as an electron acceptor Also referred to as dissimilatory sulfur￾reducing bacteria Members of the genus Desulfuromonas can grow anaerobically by coupling the oxidation of substrates such as acetate to ethanol to the reduction of elemental sulfur to hydrogen sulfide

Homoacetogenic Bacteria Obligate anaerobes Gram-positive CO2 as a terminal electron acceptor Acetate as the sole product of anaerobic respiration Acetyl-CoA pathway convert CO2 to acetate Typical species: Acetobacterium woodii and Clostridium aceticum

Homoacetogenic Bacteria Obligate anaerobes Gram-positive CO2 as a terminal electron acceptor Acetate as the sole product of anaerobic respiration Acetyl-CoA pathway convert CO2 to acetate Typical species: Acetobacterium woodii and Clostridium aceticum

Homoacetogenic Bacteria cO2 cHo-mHF→ CH:THFS-CH3 Formyl ATP THE、 Ni -Ni-CH3 -Ni co dehydrogenas CoA N Mechanism of motive force autotrophy in homoacetogenic ATP sulfate-reducing and methanogenic CH 3 C-o SCOA bacteria Acetate ATP Acetyl-COA Net: 4 H2+2 CO2- Acetate+2 H2O+H Reactions of the Acetyl-CoA Pathway

Homoacetogenic Bacteria Mechanism of autotrophy in homoacetogenic, sulfate-reducing and methanogenic bacteria Reactions of the Acetyl-CoA Pathway

Budding and Appendaged(Prosthecate) Bacteria Ancalomicrobium acetum Asticcacaulis biprosthecum Holdfast Ancalochloris perfiliewi rosthecae s stella Flagellum Swarmer cell

Budding and Appendaged (Prosthecate) Bacteria Asticcacaulis biprosthecum Ancalomicrobium adetum Ancalochloris perfilievii Stella