Methylobacterium currus sp. nov., isolated from a car air conditioning system

Int J Syst Evol Microbiol. 2018 Nov;68(11):3621-3626. doi: 10.1099/ijsem.0.003045. Epub 2018 Sep 25.

Abstract

A novel bacterial strain, designated PR1016AT, was isolated from a car air conditioning system. This rod-shaped strain showed catalase and oxidase activities, was aerobic and methylotrophic, and had a reddish pink colour. The genomic DNA G+C content of strain PR1016AT was 70.2 mol%, as determined by genome sequencing. Phylogenetic analysis based on 16S rRNA gene sequence similarity showed that strain PR1016AT was most closely related to Methylobacterium aquaticum GR16T (98.86 %), M. variabile GR3T (98.43 %), M. platani PMB 02T (98.36 %) and M. tarhaniae N4211T (98.14 %). The average nucleotide identity and digital DNA-DNA hybridization values between strain PR1016AT and M. aquaticum GR16T, M. platani PMB02T and M. variabile GR3T were 88.61, 88.14 and 87.88 %, and 36.4, 35.8 and 34.7 %, respectively. Numerous insertion sequences are present in the genome of strain PR1016AT, which has a larger genome than the four Methylobacterium species described above. Cells grew at 18-42 °C (optimum, 30 °C), at pH 4.0-9.0 (optimum, pH 7.0) and in the presence of 0-1.0 % (w/v) NaCl (optimum, 0 %). The major respiratory quinone was Q10. Fatty acid methyl ester analysis revealed that summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) was the predominant cellular fatty acid in strain PR1016AT. Two-dimensional TLC indicated that the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine. The genotypic and phenotypic characteristics indicate that strain PR1016AT represents a novel species of the genus Methylobacterium, for which the name Methylobacterium currus sp. nov. is proposed. The type strain is PR1016AT (=KACC 19662T=JCM 32670T).

Keywords: Alphaproteobacteria; Methylobacterium; taxonomy.

MeSH terms

  • Air Conditioning*
  • Automobiles*
  • Bacterial Typing Techniques
  • Base Composition
  • DNA, Bacterial / genetics
  • Fatty Acids / chemistry
  • Methylobacterium / classification*
  • Methylobacterium / genetics
  • Methylobacterium / isolation & purification
  • Nucleic Acid Hybridization
  • Phospholipids / chemistry
  • Phylogeny*
  • Pigmentation
  • RNA, Ribosomal, 16S / genetics
  • Republic of Korea
  • Sequence Analysis, DNA
  • Ubiquinone / analogs & derivatives
  • Ubiquinone / chemistry

Substances

  • DNA, Bacterial
  • Fatty Acids
  • Phospholipids
  • RNA, Ribosomal, 16S
  • Ubiquinone
  • coenzyme Q10