Serinibacter arcticus sp. nov., isolated from a thawing ancient ice wedge

A novel actinobacterium, strain K3-2 , was isolated in pure culture from a thawing ancient ice wedge at Mammoth Mountain (Eastern Siberia, Russia). Colonies of strain K3-2 were yellowish orange; cells had the fine structure typical of Gram-positive bacteria, were non-motile short rods and were non-spore-forming. Strain K3-2 was mesophilic (optimum growth at 28 °С), but capable of growing at 4 °С. The cell-wall peptidoglycan of strain K3-2 contained lysine (the diagnostic diamino acid), glutamic acid, alanine, ornithine, glycine and serine. The polar lipids were phosphatidylglycerol, lysophosphatidylserine, three unidentified phospholipids and glycolipids. The major fatty acids were anteiso-C and C . The only menaquinone detected was MK-8(H ). 16S rRNA gene analysis indicated that strain K3-2 belongs to the genus . The closest taxonomically described relatives were Kis4-28 and PS-14-7 , with 97.20 and 97.20 % 16 s rRNA gene sequence similarity, respectively. The average nucleotide identity value of the whole genome sequence between strain K3-2 and Kis4-28 was 78.9 %. DNA-DNA relatedness values between strain K3-2 and DSM 21801 (=Kis4-28 ) and VKPM Ac 2044 (=PS-14-7 ) were 41 and 47 %. Thus, strain K3-2 represents a novel species of the genus for which the name sp. nov. is proposed. The type strain is K3-2 (DSM 103859 =VKM Ас-2719 ).