Research progress on the diversity of glacial bacteria Cryobacterium

Abstract:

Glaciers, as the main cryosphere on earth, are inhabited by abundant cold-adapted microorganisms. In 1976, Inoue & Komagata isolated a psychrophilic bacterium from Antarctica. Until 1997, genus Cryobacterium was validly published with Cryobacterium psychrophilum as type species and this psychrophilic strain as type strain. The species in genus Cryobacterium were mainly distributed in cold environments such as Antarctic, Arctic, permafrost and glacier in Tibetan Plateau. Cryobacterium belongs to rare group, since its abundance is lower than other common groups in glacier environment. At present, there are 15 species in genus Cryobacterium with validly published names, including nine psychrophilic species. Different species show phenotypic divergence of thermotolerance. Therefore, Cryobacterium strains can be excellent materials for studying the evolution and speciation of bacteria in the cold environment. Cryobacterium strains can produce β-carotenoids, cold-adapted enzymes and other bioactive substances. In this paper, the distribution, biological characteristics and application potential of Cryobacterium were reviewed. The diversity of Cryobacterium was discussed by calculation and cluster analysis of the average nucleotide identity (ANI) using the whole genome sequences of Cryobacterium which were downloaded from GenBank database. The application potential of Cryobacterium in food processing, medicine and health field was discussed.