Gammaproteobacteria
Encyclopedia
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), Klebsiella pneumoniae
responsible for causing pneumonia
. Like all Proteobacteria
, the Gammaproteobacteria are Gram-negative
.
, 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.
Enterobacteriaceae
The Enterobacteriaceae is a large family of bacteria that includes many of the more familiar pathogens, such as Salmonella, Escherichia coli, Yersinia pestis, Klebsiella and Shigella. This family is the only representative in the order Enterobacteriales of the class Gammaproteobacteria in the...
(Escherichia coli
Escherichia coli
Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
), Vibrionaceae
Vibrionaceae
The Vibrionaceae are a family of Proteobacteria, given their own order. Inhabitants of fresh or salt water, several species are pathogenic, including the type species Vibrio cholerae, which is the agent responsible for cholera...
and Pseudomonadaceae
Pseudomonadaceae
The Pseudomonadaceae is a family of bacteria that includes the genera Azomonas, Azomonotrichon, Azorhizophilus, Azotobacter, Cellvibrio, Mesophilobacter, Pseudomonas , Rhizobacter, Rugamonas, and Serpens...
. An exceeding number of important pathogens belongs to this class, e.g. Salmonella
Salmonella
Salmonella is a genus of rod-shaped, Gram-negative, non-spore-forming, predominantly motile enterobacteria with diameters around 0.7 to 1.5 µm, lengths from 2 to 5 µm, and flagella which grade in all directions . They are chemoorganotrophs, obtaining their energy from oxidation and reduction...
(enteritis
Enteritis
In medicine, enteritis, from Greek words enteron and suffix -itis , refers to inflammation of the small intestine. It is most commonly caused by the ingestion of substances contaminated with pathogenic microorganisms. Symptoms include abdominal pain, cramping, diarrhea, dehydration and fever...
and typhoid fever
Typhoid fever
Typhoid fever, also known as Typhoid, is a common worldwide bacterial disease, transmitted by the ingestion of food or water contaminated with the feces of an infected person, which contain the bacterium Salmonella enterica, serovar Typhi...
), Yersinia
Yersinia
Yersinia is a genus of bacteria in the family Enterobacteriaceae. Yersinia are Gram-negative rod shaped bacteria, a few micrometers long and fractions of a micrometer in diameter, and are facultative anaerobes. Some members of Yersinia are pathogenic in humans; in particular, Y. pestis is the...
(plague), Vibrio
Vibrio
Vibrio is a genus of Gram-negative bacteria possessing a curved rod shape, several species of which can cause foodborne infection, usually associated with eating undercooked seafood. Typically found in saltwater, Vibrio are facultative anaerobes that test positive for oxidase and do not form...
(cholera), Pseudomonas aeruginosa
Pseudomonas aeruginosa
Pseudomonas aeruginosa is a common bacterium that can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has, thus, colonized many...
(lung infections in hospitalised or cystic fibrosis
Cystic fibrosis
Cystic fibrosis is a recessive genetic disease affecting most critically the lungs, and also the pancreas, liver, and intestine...
patients), Klebsiella pneumoniae
Klebsiella pneumoniae
Klebsiella pneumoniae is a Gram-negative, non-motile, encapsulated, lactose fermenting, facultative anaerobic, rod shaped bacterium found in the normal flora of the mouth, skin, and intestines....
responsible for causing pneumonia
Pneumonia
Pneumonia is an inflammatory condition of the lung—especially affecting the microscopic air sacs —associated with fever, chest symptoms, and a lack of air space on a chest X-ray. Pneumonia is typically caused by an infection but there are a number of other causes...
. Like all Proteobacteria
Proteobacteria
The Proteobacteria are a major group of bacteria. They include a wide variety of pathogens, such as Escherichia, Salmonella, Vibrio, Helicobacter, and many other notable genera....
, the Gammaproteobacteria are Gram-negative
Gram-negative
Gram-negative bacteria are bacteria that do not retain crystal violet dye in the Gram staining protocol. In a Gram stain test, a counterstain is added after the crystal violet, coloring all Gram-negative bacteria with a red or pink color...
.
Significance
The Gammaproteobacteria comprise several medically and scientifically important groups of bacteria, such as the EnterobacteriaceaeEnterobacteriaceae
The Enterobacteriaceae is a large family of bacteria that includes many of the more familiar pathogens, such as Salmonella, Escherichia coli, Yersinia pestis, Klebsiella and Shigella. This family is the only representative in the order Enterobacteriales of the class Gammaproteobacteria in the...
, Vibrionaceae
Vibrionaceae
The Vibrionaceae are a family of Proteobacteria, given their own order. Inhabitants of fresh or salt water, several species are pathogenic, including the type species Vibrio cholerae, which is the agent responsible for cholera...
and Pseudomonadaceae
Pseudomonadaceae
The Pseudomonadaceae is a family of bacteria that includes the genera Azomonas, Azomonotrichon, Azorhizophilus, Azotobacter, Cellvibrio, Mesophilobacter, Pseudomonas , Rhizobacter, Rugamonas, and Serpens...
. A number of important pathogens belongs to this class, e.g. Salmonella
Salmonella
Salmonella is a genus of rod-shaped, Gram-negative, non-spore-forming, predominantly motile enterobacteria with diameters around 0.7 to 1.5 µm, lengths from 2 to 5 µm, and flagella which grade in all directions . They are chemoorganotrophs, obtaining their energy from oxidation and reduction...
spp. (enteritis
Enteritis
In medicine, enteritis, from Greek words enteron and suffix -itis , refers to inflammation of the small intestine. It is most commonly caused by the ingestion of substances contaminated with pathogenic microorganisms. Symptoms include abdominal pain, cramping, diarrhea, dehydration and fever...
and typhoid fever
Typhoid fever
Typhoid fever, also known as Typhoid, is a common worldwide bacterial disease, transmitted by the ingestion of food or water contaminated with the feces of an infected person, which contain the bacterium Salmonella enterica, serovar Typhi...
), Yersinia pestis
Yersinia pestis
Yersinia pestis is a Gram-negative rod-shaped bacterium. It is a facultative anaerobe that can infect humans and other animals....
(plague), Vibrio
Vibrio
Vibrio is a genus of Gram-negative bacteria possessing a curved rod shape, several species of which can cause foodborne infection, usually associated with eating undercooked seafood. Typically found in saltwater, Vibrio are facultative anaerobes that test positive for oxidase and do not form...
cholerae (cholera), Pseudomonas aeruginosa
Pseudomonas aeruginosa
Pseudomonas aeruginosa is a common bacterium that can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has, thus, colonized many...
(lung infections in hospitalized or cystic fibrosis
Cystic fibrosis
Cystic fibrosis is a recessive genetic disease affecting most critically the lungs, and also the pancreas, liver, and intestine...
patients), and Escherichia coli
Escherichia coli
Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
(food poisoning). Members of Chromatium
Chromatium
Chromatium is a genus of photoautotrophic Gram-negative bacteria, also known as purple sulfur bacteria, which are found in water. These bacteria oxidize sulfide to produce sulfur which is deposited in intracellular granules of the cytoplasm. They also couple oxidation of other metals, like iron, in...
are photosynthetic and oxidize hydrogen sulfide
Hydrogen sulfide
Hydrogen sulfide is the chemical compound with the formula . It is a colorless, very poisonous, flammable gas with the characteristic foul odor of expired eggs perceptible at concentrations as low as 0.00047 parts per million...
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.
Families
- AcidithiobacillaceaeAcidithiobacillusAcidithiobacillus is a genus of Proteobacteria. Like all Proteobacteria, Acidithiobacillus is Gram-negative. The members of this genus used to belong to Thiobacillus, before they were reclassified in the year 2000....
- AeromonadaceaeAeromonadaceaeThe Aeromonadaceae are Gram-negative soil bacteria....
- AlcanivoracaceaeAlcanivoracaceaeThe Alcanivoraceae are a family of Proteobacteria....
- AlteromonadaceaeAlteromonadaceaeThe Alteromonadaceae are a family of Proteobacteria. They are now one of several families in the order Alteromonadales, including Alteromonas and its closest relatives....
- CardiobacteriaceaeCardiobacteriaceaeThe Cardiobacteriaceae are a family of Proteobacteria, given their own order. They are Gram-negative, rod-shaped, with diameters around 0.5 to 1.7 µm and lengths from 1–6 µm....
- ChromatiaceaeChromatiaceaeThe Chromatiaceae are the main family of purple sulfur bacteria. They are distinguished by producing sulfur globules within their cells. These are an intermediate in the oxidization of sulfide, which is ultimately converted into sulfate, and may serve as a reserve. Members are found in both...
- CoxiellaceaeCoxiellaceaeCoxiellaceae is a family in the order Legionellales.Coxiella burnetii is a species in this order.Another is Rickettsiella melolonthae....
- EctothiorhodospiraceaeEctothiorhodospiraceaeThe Ectothiorhodospiraceae are a family of purple sulfur bacteria, distinguished by producing sulfur globules outside of their cells. They are generally marine....
- EnterobacteriaceaeEnterobacteriaceaeThe Enterobacteriaceae is a large family of bacteria that includes many of the more familiar pathogens, such as Salmonella, Escherichia coli, Yersinia pestis, Klebsiella and Shigella. This family is the only representative in the order Enterobacteriales of the class Gammaproteobacteria in the...
- FrancisellaceaeFrancisellaFrancisella is a genus of pathogenic, Gram-negative bacteria. They are small coccobacillary or rod-shaped, non-motile organisms, which are also facultative intracellular parasites of macrophages...
- HalomonadaceaeHalomonadaceaeThe Halomonadaceae are a family of halophilic Proteobacteria.-History:The family was originally created in 1988 to contain the genera Halomonas and Deleya....
- Legionellaceae
- MethylococcaceaeMethylococcaceaeThe Methylococcaceae are a family of bacteria that obtain their carbon and energy from methane, called methanotrophs. They comprise the type I methanotrophs, in contrast to the Methylocystaceae or type II methanotrophs...
- MoraxellaceaeMoraxellaceaeThe Moraxellaceae are a family of Gammaproteobacteria, including a few pathogenic species. Other are harmless parasites of mammals and humans or occur in water or soil...
- OceanospirillaceaeOceanospirillaceaeThe Oceanospirillaceae are a family of Proteobacteria....
- PasteurellaceaePasteurellaceaePasteurellaceae comprise a large and diverse family of Gram-negative Proteobacteria with members ranging from important pathogens such as Haemophilus influenzae to commensals of the animal and human mucosa. Most members live as commensals on mucosal surfaces of birds and mammals, especially in the...
- PiscirickettsiaceaePiscirickettsiaceaeThe Piscirickettsiaceae are a family of Proteobacteria. All species are aerobe and found in water.The species Piscirickettsia salmonis is a fish pathogen bacteria and causes Piscirickettsiosis in salmonid fish....
- PseudomonadaceaePseudomonadaceaeThe Pseudomonadaceae is a family of bacteria that includes the genera Azomonas, Azomonotrichon, Azorhizophilus, Azotobacter, Cellvibrio, Mesophilobacter, Pseudomonas , Rhizobacter, Rugamonas, and Serpens...
- Shewanellaceae
- SuccinivibrionaceaeSuccinivibrionaceaeThe Succinivibrionaceae are Gram-negative soil bacteria....
- ThiotrichaceaeThiotrichaceaeThe Thiotrichaceae are a family of Proteobacteria, including Thiomargarita namibiensis, the largest known bacterium....
- VibrionaceaeVibrionaceaeThe Vibrionaceae are a family of Proteobacteria, given their own order. Inhabitants of fresh or salt water, several species are pathogenic, including the type species Vibrio cholerae, which is the agent responsible for cholera...
- XanthomonadaceaeXanthomonadaceaeThe Xanthomonadaceae are a family of Proteobacteria, given their own order....