Oceanibaculum pacificum sp. nov., isolated from hydrothermal field sediment of the south-west Pacific Ocean

Abstract

A taxonomic study was carried out on strain LMC2up-L3T, which was isolated from a polycyclic aromatic hydrocarbon-degrading consortium enriched with a sediment sample collected from a hydrothermal field of the south-west Pacific Ocean. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain LMC2up-L3T belonged to the genus Oceanibaculum, with the highest sequence similarity of 98.4 % to Oceanibaculum indicum P24T; similarity to other strains was below 93.1 %. DNA–DNA hybridization between strain LMC2up-L3T and O. indicum P24T was 31 %. rep-PCR fingerprints also differentiated strain LMC2up-L3T from O. indicum P24T. The G+C content of the chromosomal DNA was 67.7 mol%. The principal fatty acids were C16 : 1 (17.8 %), C16 : 0 (21.2 %), C18 : 1 ω7c (23.6 %), C18 : 0 (4.1 %), C18 : 1 2-OH (4.5 %) and C19 : 0 cyclo ω8c (17.4 %). The combined genotypic and phenotypic data show that strain LMC2up-L3T represents a novel species of the genus Oceanibaculum, for which the name Oceanibaculum pacificum sp. nov. is proposed, with the type strain LMC2up-L3T (=CCTCC AB 209059T =LMG 24859T =MCCC 1A02656T). An emended description of the genus Oceanibaculum is also provided.