Sandaracinobacter neustonicus sp. nov., isolated from the sea surface microlayer in the Southwestern Pacific Ocean, and emended description of the genus Sandaracinobacter

Abstract

A Gram-stain-negative, non-motile, facultatively anaerobic and rod-shaped bacterial strain, designated PAMC 28131^T, was isolated from a sea surface microlayer sample in the open water of the Pacific Ocean. Phylogenetic analysis of the 16S rRNA gene sequence of strain PAMC 28131^T revealed an affiliation to the genus Sandaracinobacter with the closest species Sandaracinobacter sibiricus RB16-17^T (sequence similarity of 98.2 %). Strain PAMC 28131^T was able to grow optimally with 0.5-1.0 % NaCl and at pH 6.5-7.0 and 30 °C. The polar lipids were phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, an unidentified aminolipid, an unidentified glycolipid and an unidentified lipid. The major cellular fatty acids (>10 %) were C_{18 : 1} ω6c and/or C_{18 : 1} ω7c, (42.6 %), C_{17 : 1} ω6c (19.3 %) and C_{16 : 1} ω6c and/or C_{16 : 1} ω7c (15.8 %), and the respiratory quinone was Q-10. The genomic DNA G+C content was 65.3 mol%. The phylogenetic, phenotypic and chemotaxonomic data showed that strain PAMC 28131^T could be clearly distinguished from S. sibiricus RB16-17^T. Thus, strain PAMC 28131^T should be classified as representing a novel species in the genus Sandaracinobacter, for which the name Sandaracinobacter neustonicus sp. nov. is proposed. The type strain is PAMC 28131^T (=KCCM 43127^T=JCM 30734^T).

Keywords: Pacific Ocean; Sandaracinobacter neustonicus; new species; sea surface microlayer.