Characterization of Micrococcus antarcticus sp nov., a psychrophilic bacterium from Antarctica

A Gram-positive, cold-adapted, aerobic, spherical actinobacterium (strain T2(T)) with a quite low cardinal growth temperature was isolated from Chinese Great-Wall station in Antarctica. Sequence comparisons of the 16S rDNA indicated the isolate to be a phylogenetic member of the genus Micrococcus. family Micrococcaceae, in which it represents a novel lineage. The phylogenetic distinctness of the isolate with respect to the type strains Micrococcus luteus and Micrococcus lylae was supported by DNA-DNA similarity values of less than 40%. Chemotaxonomic properties supported the placement of the isolate in the genus Micrococcus. The diagnostic diamino acid of the cell-wall peptidoglycan is lysine. The predominant menaquinones are MK-8 and MK-8(H-2). The G+C content of the DNA of the isolate is 66.4 mol%. Genotypic. morphological and physiological characteristics were used to describe a new species of Micrococcus, for which the name Micrococcus antarcticus is proposed. The type strain is T2(T) (= AS 1.2372(T)).