Mucilaginibacter glaciei sp. nov. and Mucilaginibacter pankratovii sp. nov., isolated from a glacier on the Tibetan Plateau

Abstract

Two Gram-stain-negative, aerobic, rod-shaped, non-motile, bacterial strains, designated as ZB1P21T and ZT4R22T, were isolated from ice and cryoconite samples collected from Zepu glacier on the Tibetan Plateau, PR China. The phylogenetic analysis of 16S rRNA gene showed that the two strains belong to the genus Mucilaginibacter . Strain ZB1P21T showed the highest similarity to Mucilaginibacter rigui WPCB133T (97.35 %), while strain ZT4R22T showed the highest similarity to Mucilaginibacter gilvus F01003T (99.11 %). The average nucleotide identity values between the two novel strains and their closest relatives were 79.42 and 85.72 % respectively. The two novel strains contained MK-7 as the major menaquinone, and summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c), iso-C15:0, iso-C17 : 03-OH and C16 : 1 ω5c as the major fatty acids. The major polar lipid of the two novel strains were phosphatidylethanolamine. Based on these data, we propose two novel species, Mucilaginibacter glaciei sp. nov. (ZB1P21T=CGMCC 1.23981T=NBRC 113932T) and Mucilaginibacter pankratovii sp. nov. (ZT4R22T=CGMCC 1.23487T=NBRC 113931T).

Mucilaginibacter aurantiaciroseus sp. nov. and Mucilaginibacter flavidus sp. nov., isolated from Renlongba glacier on the Tibetan Plateau

“…The samples were analysed by gas chromatography on an Agilent 6890 N gas chromatograph using the TSBA6 database. Strains RB4R14 T and RT5R15 T contained MK-7 as the predominant menaquinone, which is typical for members of the genus Mucilaginibacter [1][2][3][5][6][7][8][9][10][11]. Both strains RB4R14 T and RT5R15 T contained phosphatidylethanolamine as a major polar lipid.…”

“…Strains RB4R14 T and RT5R15 T contained MK-7 as the predominant menaquinone, which is typical for members of the genus Mucilaginibacter [1–3, 5–11]. Both strains RB4R14 T and RT5R15 T contained phosphatidylethanolamine as a major polar lipid.…”

“… Mucilaginibacter species have been found in diverse niches, such as fresh water [5], soil [6], plant stem [7] and marine sand [8]. Some species were even found in the cryosphere, such as Mucilaginibacter gilvus in Antarctic [9], Mucilaginibacter soli in Arctic [10] and Mucilaginibacter pankratovii in glacier [11]. Most species of the genus Mucilaginibacter can produce extracellular polymeric substances and pigments [12, 13].…”

Mucilaginibacter rivuli sp. nov., isolated from a water rivulet

“…The menaquinone-7 (MK-7) is the predominant respiratory quinone. The major cellular fatty acids are iso-C 15 : 0 , iso-C 17 : 0 3-OH and summed feature 3 (C 16 : 1 ω7c and/or C 16 : 1 ω6c) [3][4][5][6][7][8][9][10]. Some species are characterized by producing exopolysaccharides and degrading cellulose, hemicellulose, pectin, xylan and laminarin, and have potential plant-growth-promoting abilities [13,14].…”

“…So far, this genus consists of 71 species with valid names (www.bacterio.net/genus/mucilaginibacter). Members of this genus have been isolated from diverse environmental habitats such as soil, rhizosphere, heavy-metal-contaminated paddy field, glacier, plant stem and dried rice straw [3][4][5][6][7][8][9][10][11][12]. They are Gram-stain-negative, non-spore-forming and non-motile rods.…”