Alpinimonas psychrophila gen. nov., sp. nov., an actinobacterium of the family Microbacteriaceae isolated from alpine glacier cryoconite

A Gram-type positive, Gram-reaction variable, non-motile, psychrophilic actinobacterium, designated Cr8-25^T, was isolated from alpine glacier cryoconite and was able to grow well over a temperature range of 1–15 °C. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain Cr8-25^T belonged to the family Microbacteriaceae and showed highest 16S rRNA gene sequence similarity with Klugiella xanthotipulae 44C3^T (97.0 %). However, strain Cr8-25^T could be differentiated from the type strain of K. xanthotipulae on the level of genomospecies by a DNA–DNA relatedness value of only 37.2 %. Strain Cr8-25^T contained a cell-wall peptidoglycan that was cross-linked according to the B-type, which is based on 2,4-diaminobutyric acid. The cell wall contained the sugars galactose, fucose and rhamnose. The predominant cellular fatty acids of strain Cr8-25^T were C_15 : 0 anteiso (64.6 %) and iso-C_16 : 0 (22.5 %) and the major menaquinones were MK-11 and MK-10. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and unknown glycolipids. The G+C content of the genomic DNA was 58.8 mol%. On the basis of the phenotypic characteristics, phylogenetic and chemotaxonomic analyses and DNA–DNA relatedness data, strain Cr8-25^T represents a novel species of a new genus in the family Microbacteriaceae, for which the name Alpinimonas psychrophila gen. nov., sp. nov. is proposed. The type strain is Cr8-25^T ( = DSM 23737^T = LMG 26215^T).