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 levicorallinum 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.