Rahnella sikkimica sp. nov., a novel cold-tolerant bacterium isolated from the glacier of Sikkim Himalaya with plant growth-promoting properties

Extremophiles. 2022 Nov 15;26(3):35. doi: 10.1007/s00792-022-01283-y.

Abstract

The current study describes a novel species with the strain name ERMR1:05T isolated from the forefield soil of East Rathong Glacier in West Sikkim Himalaya (India). The isolate was facultatively anaerobic, gram-stain negative, non-spore-forming, rod-shaped, and oxidase negative. Whole-genome-based bacterial core gene phylogenetic analysis placed the strain in the genus Rahnella, well separated from Rouxiella spp. The digital DNA-DNA hybridisation and average nucleotide identity values between strain ERMR1:05T and other members of genus Rahnella were below the proposed thresholds for the species delineation. Based on these results, a new species, Rahnella sikkimica sp. nov., is proposed with strain ERMR1:05T (CIP 111636T, MTCC 12598T) as the type strain. The bacterium showed upregulation of cold-stress genes in cold conditions. Additionally, the genome analysis of the bacterium showed the presence of plant growth-promotion factors suggesting its role in crop improvement in cold hilly regions.

Keywords: Cold-responsive genes; East Rathong Glacier; Novel species; Rahnella; Whole genome sequence.

MeSH terms

  • Bacterial Typing Techniques
  • Base Composition
  • DNA, Bacterial / genetics
  • Fatty Acids
  • Ice Cover* / microbiology
  • Phospholipids
  • Phylogeny
  • RNA, Ribosomal, 16S / genetics
  • Rahnella* / genetics
  • Sequence Analysis, DNA
  • Sikkim

Substances

  • RNA, Ribosomal, 16S
  • DNA, Bacterial
  • Fatty Acids
  • Phospholipids