Salipiger mangrovisoli sp. nov., isolated from mangrove soil and the proposal for the reclassification of Paraphaeobacter pallidus as Salipiger pallidus comb. nov

Int J Syst Evol Microbiol. 2021 Jul;71(7). doi: 10.1099/ijsem.0.004892.

Abstract

A novel Gram-stain-negative, aerobic and rod-shaped bacterial strain designated as 6D45AT was isolated from mangrove soil and characterized using a polyphasic taxonomic approach. Strain 6D45AT was found to grow at 10-37 °C (optimum, 28 °C), at pH 6.0-9.0 (optimum, 7.0) and in 0-5 % (w/v) NaCl (optimum, 2%). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 6D45AT fell into the genus Salipiger and shared 99.1 % identity with the closest type strain Salipiger pacificus CGMCC 1.3455T and less than 97.2 % identity with other type strains of this genus. The 34.8 % digital DNA-DNA hybridization (dDDH) and 88.3 % average nucleotide identity (ANI) values between strain 6D45AT and the closest relative above were well below recognized thresholds of 70 % DDH and 95-96 % ANI for species definition, implying that strain 6D45AT should represent a novel genospecies. The phylogenomic analysis indicated that strain 6D45AT formed an independent branch distinct from reference strains. The predominant cellular fatty acid of strain 6D45AT was summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c, 66.9 %); the polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, two unidentified aminolipids, two unidentified glycolipids and an unknown lipid; the respiratory quinone was Q-10. The genomic DNA G+C content was 66.5 mol %. Based on the phenotypic and genotypic characteristics, strain 6D45AT is concluded to represent a novel species of the genus Salipiger, for which the name Salipiger mangrovisoli sp. nov., is proposed. The type strain of the species is 6D45AT (=GDMCC 1.1960T=KCTC 82334T). We also propose the reclassification of Paraphaeobacter pallidus as Salipiger pallidus comb. nov. and 'Pelagibaca abyssi' as a species of the genus Salipiger.

Keywords: Salipiger mangrovisoli; genotypes and phenotypes; polyphasic taxonomy; reclassification.

MeSH terms

  • Alphaproteobacteria / classification*
  • Alphaproteobacteria / isolation & purification
  • Bacterial Typing Techniques
  • Base Composition
  • China
  • DNA, Bacterial / genetics
  • Fatty Acids / chemistry
  • Glycolipids / chemistry
  • Nucleic Acid Hybridization
  • Phospholipids / chemistry
  • Phylogeny*
  • RNA, Ribosomal, 16S / genetics
  • Rhodobacteraceae / classification
  • Sequence Analysis, DNA
  • Soil Microbiology*
  • Ubiquinone / analogs & derivatives
  • Ubiquinone / chemistry
  • Wetlands

Substances

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

Supplementary concepts

  • Paraphaeobacter pallidus
  • Pelagibaca abyssi