Methylobacterium radiodurans sp. nov., a novel radiation-resistant Methylobacterium

Arch Microbiol. 2021 Aug;203(6):3435-3442. doi: 10.1007/s00203-021-02293-8. Epub 2021 Apr 24.

Abstract

A Gram-negative, aerobic, flagellated, rod-shaped, and pink-pigmented bacterium, strain 17Sr1-43 T, was isolated from a soil sample collected in Nowongu, Seoul, Korea. The isolate could grow at 18-37 °C (optimum, 28-30 °C), pH 6.0-8.0 (optimum, pH 7.0) and in the presence of 0-1.0% (w/v) NaCl (optimum, 0%) with aeration. The major cellular fatty acids were summed feature 8 (C18:1 ω7c and/or C18:1 ω6c) and summed feature 2 (iso-C16:1 I and/or C14:0 3-OH). The predominant respiratory quinone was Q-10 and the major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, phospholipid, and diphosphatidylglycerol. The G + C content of genomic DNA was 69.1 mol%. Strain 17Sr1-43 T was closely related to Methylobacterium gregans KACC 14808 T (98.4% 16S rRNA gene sequence similarity), Methylobacterium hispanicum KACC 11432 T (97.9%), and Methylobacterium phyllosphaerae CBMB27T (96.1%). The complete genome of strain 17Sr1-43 T contains essential genes related to DNA repair processes including bacterial RecBCD dependent pathway and UmuCD system. Based on the phenotypic, genotypic, and chemotaxonomic characteristics, strain 17Sr1-43 T represents a novel species in the genus Methylobacterium, for which the name Methylobacterium radiodurans sp. nov. is proposed. The type strain is strain 17Sr1-43 T (= KCTC 52906 T = NBRC 112875 T).

Keywords: Gamma-ray tolerance; Methylobacterium; Novel species; Polyphasic study.

MeSH terms

  • DNA Repair / genetics
  • Methylobacterium* / classification
  • Methylobacterium* / genetics
  • Methylobacterium* / radiation effects
  • Nucleic Acid Hybridization
  • Phospholipids / analysis
  • Phylogeny
  • RNA, Ribosomal, 16S / genetics
  • Radiation Tolerance
  • Soil Microbiology*
  • Species Specificity

Substances

  • Phospholipids
  • RNA, Ribosomal, 16S

Supplementary concepts

  • Methylobacterium gregans
  • Methylobacterium hispanicum
  • Methylobacterium phyllosphaerae