Gammaproteobacteria

Gammaproteobacteria
Vibrio cholerae
Scientific classification
Domain:	Bacteria
Phylum:	Proteobacteria
Class:	Gammaproteobacteria
Orders
Acidithiobacillales Acidithiobacillaceae Thermithiobacillaceae Aeromonadales Aeromonadaceae Succinivibrionaceae Alteromonadales Alteromonadaceae Celerinatantimonadaceae Colwelliaceae Ferrimonadaceae Idiomarinaceae Moritellaceae Pseudoalteromonadaceae Psychromonadaceae Shewanellaceae Cardiobacteriales Cardiobacteriaceae Chromatiales Chromatiaceae Ectothiorhodospiraceae Granulosicoccaceae Halothiobacillaceae Thioalkalispiraceae "Enterobacteriales" Enterobacteriaceae Legionellales Coxiellaceae Legionellaceae Methylococcales Crenotrichaceae Methylococcaceae Oceanospirillales Alcanivoracaceae Hahellaceae Halomonadaceae Litoricolaceae Oceanospirillaceae Oleiphilaceae "Saccharospirillaceae" Pasteurellales Pasteurellaceae Pseudomonadales Moraxellaceae Pseudomonadaceae "Salinisphaerales" "Salinisphaerales" Thiotrichales Francisellaceae Piscirickettsiaceae Thiotrichaceae "Vibrionales" Vibrionaceae Xanthomonadales Sinobacteraceae Xanthomonadaceae

Gammaproteobacteria are a class of several medically, ecologically, and scientifically important groups of bacteria. An exceeding number of important pathogens belongs to this class. Like all Proteobacteria, the Gammaproteobacteria are Gram-negative.

Significance

The Gammaproteobacteria comprise several medically and scientifically important groups of bacteria, such as the Enterobacteriaceae, Vibrionaceae and Pseudomonadaceae. A number of important pathogens belongs to this class, e.g. Salmonella spp. (enteritis and typhoid fever), Yersinia pestis (plague), Vibrio cholerae (cholera), Pseudomonas aeruginosa (lung infections in hospitalized or cystic fibrosis patients), and Escherichia coli (food poisoning). Important plant pathogens such as Xanthomonas axonopodis pv. citri (citrus canker) and Pseudomonas syringae pv. actinidiae (kiwifruit Psa outbreak) are also Gammaproteobacteria. Members of Chromatium are photosynthetic and oxidize hydrogen sulfide instead of water, producing sulfur as a waste product. Some Gammaproteobacteria are methane oxidizers, and many of them are in symbiosis with geothermic ocean vent dwelling animals.

Phylogeny

Due to a single genus, Acidithiobacillus, the Gammaproteobacteria class is paraphyletic to Betaproteobacteria (reviewed in Proteobacteria#Taxonomy).

Phylogeny of Gammaproteobacteria

Acidithiobacillus Betaproteobacteria Xanthomonadales Chromatiales Methylococcus Beggiatoa Legionellales Ruthia, Vesicomyosocius, Thiomicrospira, Dichelobacter, Francisella Moraxellaceae, Alcalinovorax Saccharophagus, Reinekea Oceanospirillaceae Marinobacter Pseudomonadaceae Pseudoalteromonadaceae, Alteromonas, Idiomarinaceae Shewanellaceae Psychromonadaceae Aeromonas Vibrionales Pasteurellales Enterobacteriales

Phylogeny of Gammaproteobacteria after Not all orders are monophyletic, consequently families or genera are shown for Pseudomonadales, Oceanospirillales, and Alteromonadales. In the case of singleton orders, the genus is shown. (In bacterial taxonomy, orders have the suffix -ales, while families have -aceae.)

See also

• Betaproteobacteria
• Proteobacteria

External links

• Gammaproteobacteria at the US National Library of Medicine Medical Subject Headings (MeSH)