Shewanella polaris sp. nov., a psychrotolerant bacterium isolated from Arctic brown algae

Abstract

A Gram-stain-negative, facultatively anaerobic, flagellated and rod-shaped bacterium, designated strain SM1901T, was isolated from a brown algal sample collected from Kings Bay, Svalbard, Arctic. Strain SM1901T grew at −4‒30 °C and with 0–7.0 % (w/v) NaCl. It reduced nitrate to nitrite and hydrolysed DNA and Tween 80. Results of phylogenetic analyses based on 16S rRNA gene sequences indicated that strain SM1901T was affiliated with the genus Shewanella , showing the highest sequence similarity to the type strain of Shewanella litoralis (97.5%), followed by those of Shewanella vesiculosa , Shewanella livingstonensis and Shewanella saliphila (97.3 % for all three). The major cellular fatty acids were summed feature 3 (C16 : 1 ω7с and/or C16 : 1 ω6с), C16 : 0, C18 : 0, iso-C15 : 0 and C17 : 1 ω8с and the major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. The respiratory quinones were ubiquinones Q-7, Q-8, menaquinones MK-7(H) and MK-8. The genome of strain SM1901T was 4648537 nucleotides long and encoded a variety of cold adaptation related genes, providing clues for better understanding the ecological adaptation mechanisms of polar bacteria. The genomic DNA G+C content of strain SM1901T was 40.5 mol%. Based on the polyphasic evidence presented in this paper, strain SM1901T was considered to represent a novel species, constituting a novel psychrotolerant lineage out of the known SF clade encompassed by polar Shewanella species, within the genus Shewanella , for which the name Shewanella polaris sp. nov. is proposed. The type strain is SM1901T (=KCTC 72047T=MCCC 1K03585T).

Shewanella nanhaiensis sp. nov., a marine bacterium isolated from sediment of South China Sea, and emended descriptions of Shewanella woodyi, Shewanella hanedai and Shewanella canadensis

“…S3). Phosphatidylethanolamine and phosphatidylglycerol were the major and common polar lipids of strain NR704-98 T , S. woodyi MS32 T and S. hanedai 281 T , which was consistent with profiles previously reported for Shewanella species [45,46]. Strains NR704-98 T and S. woodyi MS32 T contained one unidentified aminophospholipid that was absent in S. hanedai 281 T .…”

Shewanella cyperi sp. nov., a facultative anaerobic bacterium isolated from mangrove sediment

“…The respiratory quinones of strains FJAT-53720 T and FJAT-53726 were ubiquinones Q-7, Q-8 and menaquinones MK-7, which were consistent with those of other species of the genus Shewanella [21,22].…”

Mechanisms of temperature acclimatisation in the psychrotolerant green alga Coccomyxa subellipsoidea C‐169 (Trebouxiophyceae)

“…Despite numerous studies on cold adaptation, there is little understanding of the acclimatisation of psychrotolerant algae. There are only a few publications on the physiology and genetics of psychrotolerants (Barcyte et al, 2018; Cao et al, 2016; Cha et al, 2020; Lee et al, 2019; Peng et al, 2021; Wang et al, 2020), and the publication of Cao et al (2016) is one of the very few examples of research on the adaptivity of psychrotolerant algae (Arctic Chlorella sp.) to different temperatures.…”