Alteromonadales
Shewanella oneidensis
The Alteromonadales are an order of Gammaproteobacteria. Originally it contained only one family, the Alteromonadaceae, currently it consists of eight families. It is like all Proteobacteria are Gram negative bacteria. Many of the species are found in sea water and often in extreme habitats such as the deep sea.
Features
They are gram- negative, straight or slightly curved rod-shaped and usually flagellate with a polar flagellum bacteria.
Some species are strictly aerobic, so need oxygen to grow, others are facultative anaerobes and also show growth under oxygen exclusion. Some of the latter species use under the anaerobic conditions as the fermentation pathway, otherwise a respiratory metabolism.
The oxidase and catalase test is positive in most species.
Ecology
Types of Alteromonadales were found in many areas of the sea, near the coast and open sea water, on the seabed in the deep sea as well as on fish and various invertebrates.
Many extremophiles, ie adapted to extreme environmental conditions, species are represented in this order. To tolerate some species low temperatures up to the freezing point ( psychrotolerant ) or even dependent on low temperatures for growth ( psychrophilic ). Shewanella amazonensis psychrotolerant as is the nature tolerate low temperatures up to 4 ° C, optimum growth at 37 ° C. Colwellia psychrerythraea psychrophilic is, it grows in the liquid medium at temperatures between 0 and 19 ° C, at temperatures higher than 20 ° C, no growth is possible. Some, such as Types of Glaciecola and Shewanella hanedai colonize Antarctic Eisdiatomeen.
Some of the psychrophilic species are also barophil or barotolerant, they live in deep sea water or in the deep sea, there exists at temperatures 2-3 ° C high pressure. Psychrophilic and so tolerated barotolerante type Shewanella benthica high pressure ratios and shows growth at a pressure of 400-600 Mpa, but is capable of growing even under atmospheric pressure. The optimum growth temperature at atmospheric pressure is about 5 ° C. The bacterium is an obligate Moritella yayanosii barophil, so rely on high pressure below 50 MPa, it is unable to grow in the position. Another example of deep-water fish is at depths of 4000 - 5000 m isolated genus Idiomarina
Also halophilic, in environments with high concentrations of salt -living bacteria are represented in the order, such as Moritella.
System
The genera Teredinibacter and Candidatus Endobugula be classified provisionally here without further classification. In the Regulations, the following families are included:
- Alteromonadaceae Ivanova and Mikhailov 2001
- Celerinatantimonadaceae Cramer et al. 2011
- Colwelliaceae Ivanova et al. 2004
- Ferrimonadaceae Ivanova et al. 2004
- Idiomarinaceae Ivanova et al. 2004 emend. Jean et al. 2006
- Moritellaceae Ivanova et al. 2004
- Pseudoalteromonadaceae Ivanova et al. 2004
- Psychromonadaceae Ivanova et al. 2004
- Shewanellaceae Ivanova et al. 2004