Gammaproteobacteria is a class of several medically, ecologically and scientifically important groups of bacteria, such as the Enterobacteriaceae (Escherichia coli), Vibrionaceae and Pseudomonadaceae. An exceeding number of important pathogens belongs to this class, e.g. Salmonella (enteritis and typhoid fever), Yersinia (plague), Vibrio (cholera), Pseudomonas aeruginosa (lung infections in hospitalised or cystic fibrosis patients), and Klebsiella pneumoniae responsible for causing pneumonia. Like all Proteobacteria, the Gammaproteobacteria are Gram-negative.
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). Members of Chromatium are photosynthetic and oxidize hydrogen sulfide instead of water, producing sulfur as excrement. Some Gammaproteobacteria are methane oxidizers, and many of them are in symbiosis with geothermic ocean vent dwelling animals.
Due to a single genus, Acidithiobacillus, Gammaproteobacteria is paraphyletic to Betaproteobacteria (reviewed in Proteobacteria#Taxonomy).
|Phylogeny of Gammaproteobacteria
|Phylogeny of Gammaproteobacteria after Not all orders are monophyletic, consequently families or genera are shown for Psuedomonadales, Oceanospirillales, Alteromonadales. In the case of singleton orders, the genus is shown. (In bacterial taxonomy, orders have the suffix -ales, while families have -aceae.)
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