Pelagovum pacificum gen. nov., sp. nov., a novel member of the family Rhodobacteraceae isolated from surface seawater of the Mariana Trench

Int J Syst Evol Microbiol. 2020 Dec;70(12):6155-6162. doi: 10.1099/ijsem.0.004512.


A Gram-stain-negative, aerobic, ovoid-rod-shaped bacterium, designated strain SM1903T, was isolated from surface seawater of the Mariana Trench. The strain grew at 15-37 °C (optimum, 35 °C) and with 1-15 % (optimum, 4 %) NaCl. It hydrolysed aesculin but did not reduce nitrate to nitrite and hydrolyse Tween 80. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain SM1903T formed a separate lineage within the family Rhodobacteraceae, sharing the highest 16S rRNA gene sequence similarity with type strains of Pseudooceanicola antarcticus (95.7 %) and Roseisalinus antarcticus (95.7 %). In phylogenetic trees based on single-copy OCs and whole proteins sequences, strain SM1903T fell within a sub-cluster encompassed by Oceanicola granulosus, Roseisalinus antarcticus and Histidinibacterium lentulum and formed a branch adjacent to Oceanicola granulosus. The major cellular fatty acids were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c), C16 : 0 and 11-methyl-C18 : 1 ω7c. The polar lipids mainly comprised phosphatidylglycerol, phosphatidylcholine, one unidentified lipid, one unidentified aminolipid, and one unidentified glycolipid. The solo respiratory quinone was ubiquinone-10. The genomic DNA G+C content of strain SM1903T was 66.0 mol%. Based on the results of phenotypic, chemotaxonomic, and phylogenetic characterization for strain SM1903T, it is considered to represent a novel species of a novel genus in the family Rhodobacteraceae, for which the name Pelagovum pacificum gen. nov., sp. nov. is proposed. The type strain is SM1903T (=MCCC 1K03608T=KCTC 72046T).

Keywords: Pelagovum pacificum gen. nov., sp. nov.; Rhodobacteraceae.

MeSH terms

  • Bacterial Typing Techniques
  • Base Composition
  • DNA, Bacterial / genetics
  • Fatty Acids / chemistry
  • Pacific Ocean
  • Phospholipids / chemistry
  • Phylogeny*
  • RNA, Ribosomal, 16S / genetics
  • Rhodobacteraceae / classification*
  • Rhodobacteraceae / isolation & purification
  • Seawater / microbiology*
  • Sequence Analysis, DNA
  • Ubiquinone / analogs & derivatives
  • Ubiquinone / chemistry


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