The genus Psychrobacter comprises psychrophilic to psychrotolerant, halotolerant, aerobic, non-motile, Gram-negative coccobacilli and was first described as a genus separate from Acinetobacter in 1986. Known Psychrobacter species are capable of reproduction at temperatures ranging from −10 to 37 °C. Examples range from the strict (stenothermal) psychrophile Psychrobacter frigidicola (0 to 22 °C, T opt=15 °C) to the eurythermal psychrophile Psychrobacter okhotskensis (−5 to 35 °C, T opt=25 °C). While Psychrobacter species are cold-adapted, other distinguishing characteristics include salt tolerance, natural competence and cellular fatty acid content. Psychrobacter species have been isolated from a variety of low-temperature marine environments including Antarctic sea ice, ornithogenic soil and sediments, the stomach contents of the Antarctic krill Euphausia, seawater (north-western Pacific Ocean, 300 m depth), the deep sea and the internal tissues of a marine ascidian; other sources of Psychrobacter include pigeon faeces, fish, poultry, dairy products, fermented seafood, clinical sources and an infected lamb. The mechanisms used by these bacteria to resist cold temperatures has been subject of study in the last decade. Some differential components have found, such as specific components of the bacterial LPS. One example is 2,3,4-triacetamido-2,3,4-trideoxy-l-arabinose, a O-specific polysaccharide from the lipopolysaccharide of Psychrobacter cryohalolentis. This sugar has a specific biosynthesis pathway, that includes some enzymes like the one you are looking at: a specific Pcryo_0619 N-acetyltransferase, determined by x-ray crystallography (PDB code: 8VRM)

#molecularart ... #xray ... #psychrobacter .. #cold ... #LPS ... #polysaccharide

Structure rendered with @proteinimaging and depicted with @corelphotopaint