Cryobacterium ruanii sp. Nov. and cryobacterium breve sp. nov., isolated from glaciers

Abstract

Strains Sr36T and TMT4-23T were isolated from No. 1 glacier in Xinjiang Uygur Autonomous Region and Toumingmengke glacier in Gansu Province, PR China, respectively. They were Gram-stain-positive and rod-shaped micro-organisms. The optimum growth temperature of the two strains was 10–14 °C. Phylogenetic analysis showed that the two strains were related to members of the genus Cryobacterium. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between strain Sr36T and its close relatives Cryobacterium luteum Hh15T, Cryobacterium aureum Hh31T, Cryobacterium levi-corallinum Hh34T and Cryobacterium flavum Hh8T were 81.16–87.24 and 28.0–32.5 %, respectively. The ANI and dDDH values between strain TMT4-23T and its close relative Cryobacterium psychrotolerans 0549T were 81.16 and 22.3 %. The polar lipids of strain Sr36T were diphosphatidylglycerol, phosphatidylglycerol, one unidentified glycolipid and three unidentified lipids. The polar lipids of strain TMT4-23T were diphosphatidylglycerol, phosphatidylglycerol, one unidentified glycolipid, one unidentified phospholipid and six unidentified lipids. The major fatty acids of strain Sr36T were anteiso-C15: 0, iso-C16: 0, anteiso-C17: 0 and anteiso-C15: 1. The major fatty acids of strain TMT4-23T were anteiso-C15: 0, anteiso-C17: 0, iso-C16: 0, anteiso-C15: 1 and iso-C15: 1. Both strains contained 2,4-diaminobutyric acid and their predominant menaquinone was MK-10. On the basis of the phenotypic, phylogenetic and genotypic data, two novel species Cryobacterium ruanii sp. nov. (type strain = Sr36T=CGMCC 1.9275T=NBRC 113797T) and Cryobacterium breve sp. nov. (type strain =TMT4-23T=CGMCC 1.9556T=NBRC 113800T) are proposed.