Description of Gemmobacter aestuarii sp. nov., isolated from estuarine surface water and reclassification of Cereibacter changlensis as Gemmobacter changlensis Chen et al. 2013

Arch Microbiol. 2020 Jul;202(5):1035-1042. doi: 10.1007/s00203-020-01809-y. Epub 2020 Jan 16.


A Gram-stain-negative, tyrosine-metabolizing, non-motile, strictly aerobic, non-spore-forming, rod-shaped marine bacterium, designated strain CC-PW-75T, was isolated from the estuarine water off Pintung, Taiwan. Strain CC-PW-75T formed a distinct phyletic lineage associated with Gemmobacter species, sharing the highest 16S rRNA gene sequence similarity with G. megaterium CF17T and G. straminiformis CAM-8T (96.0% each) followed by G. aquatilis IFAM 1031T and G. nectariphilus AST4T (95.8% each). Analysis of the draft genome (3.76 Mbp) revealed the presence of genes encoding light-harvesting complexes, photosynthetic reaction centers and proteins involved in the metabolism of CO, CO2, HCO3 and H2S. However, bacteriochlorophyll a was not detected. Average nucleotide identity values between the genome sequence of CC-PW-75T and the related Gemmobacter species (n = 6) were estimated to be 72.8-76.3%. Polar lipid analysis revealed the presence of phosphatidylglycerol, phosphatidylethanolamine and an unidentified lipid in major amounts, and phosphatidylmonomethylethanolamine, phosphatidylcholine, an unidentified aminolipid and an unidentified lipid in minor amounts. C18:1ω7c and/or C18:1ω6c, C18:0 and C18:1ω7c 11-methyl were identified to be major fatty acids. The DNA G + C content was 66.2 mol% (draft genome sequence). Ubiquinone-10 (Q-10) was the sole respiratory quinone. Based on the polyphasic taxonomic evidence, CC-PW-75T is most likely a novel species of the genus Gemmobacter, affiliated to the family Rhodobacteraceae, for which the name Gemmobacter aestuarii sp. nov. is proposed. The type strain is CC-PW-75T (= JCM 19754T = BCRC 80759T). Also, we propose the reclassification of Cereibacter changlensis as Gemmobacter changlensis Chen et al. 2013 using the polyphasic data presented in this study.

Keywords: Bacteriochlorophyll; Carbon monoxide dehydrogenase; Light-harvesting complex; Rhodobacteraceae; RuBisCO.

MeSH terms

  • Bacterial Typing Techniques
  • Base Composition / genetics
  • DNA, Bacterial / genetics
  • Estuaries
  • Fatty Acids / analysis
  • Phospholipids / analysis
  • Phylogeny
  • RNA, Ribosomal, 16S / genetics
  • Rhodobacteraceae / classification*
  • Rhodobacteraceae / genetics
  • Rhodobacteraceae / isolation & purification*
  • Rhodobacteraceae / metabolism
  • Sequence Analysis, DNA
  • Taiwan
  • Ubiquinone / analogs & derivatives
  • Ubiquinone / metabolism
  • Water


  • DNA, Bacterial
  • Fatty Acids
  • Phospholipids
  • RNA, Ribosomal, 16S
  • Water
  • Ubiquinone
  • coenzyme Q10
  • Ubiquinone Q2

Supplementary concepts

  • Cereibacter changlensis