The proteins which are the focus of interest in this article come from
different phylogenetically-related obligate and facultative psychrophilic Gram-negative bacteria. Photobacterium profundum str. SS9, which belongs to Gammaproteobacteria, Vibrionaceae family, was isolated from the Sulu Trough associated with Amphipoda Androgen Receptor animal study at a depth of 2551 m. It is a psychrophilic and moderately barophilic bacterium with an optimum growth temperature and pressure of 15°C and 20 MPa, respectively [8]. P. profundum SS9 is a genetically tractable model system for studies of low-temperature and high-pressure adaptation [9]. Desulfotalea psychrophila, which belongs to Deltaproteobacteria, Desulfobulbaceae family, is a sulfate-reducing bacteria isolated from permanently cold Arctic sediments off the coast of Svalbard, Norway [10]. Flavobacterium psychrophilum, belongs to Bacteroidetes, Flavobacteriaceae family, is a facultative
psychrophilic bacterium and one of the most serious of the fish pathogens [11]. The Psychrobacter arcticus and Psychrobacter cryohalolentis strains, which belong to Gammaproteobacteria, Moraxellaceae family, were isolated from permafrost samples taken from the Kolyma lowland region of Siberia, Russia [12]. P. arcticus was selleck chemicals llc a model organism for studies on the mechanisms of adaptation to low temperatures [13]. Psychromonas ingrahamii bacterium, which belongs to Gammaproteobacteria, Psychromonadaceae family, was isolated from a sea ice core collected on Point Barrow in Alaska, USA. The bacterium grows well at NaCl concentrations of 1-10% and at temperatures of −12 to 10°C; no growth is CX-6258 observed
at 15°C, and the optimal growth temperature is 5°C. Psychromonas ingrahamii is the only bacterium growing at such a low temperature to have been described to date [14]. Psychroflexus torquis, which belongs to Bacteroidetes, Flavobacteriaceae family, is isolated from Antarctic sea ice psychrophilic bacterium. The representatives of this species possess an uncommon characteristic, the ability to synthesize see more polyunsaturated fatty acids [15]. The aim of this study was to clone and overexpress D. psychrophila, F. psychrophilum, P. arcticus, P. cryohalolentis, P. ingrahamii, P. profundum, and P. torquis ssb-like genes in E. coli, purify the gene products and study their biochemical properties. Results Sequence analysis The sequence analysis of the D. psychrophila (GenBank accession No. NC_006138; [16]), F. psychrophilum (GenBank accession No. NC_009613; [17]), P. arcticus (GenBank accession No. NC_007204; [18]), P. cryohalolentis (GenBank accession No. NC_007969; Gene Bank Project: PRJNA58373), P. ingrahamii (GenBank accession No. NC_008709; [19]), P. profundum (GenBank accession No. NC_006370; [20]) and P. torquis (GenBank accession No.