Croceicoccus ponticola sp. nov., a lipolytic bacterium isolated from seawater

Abstract

A lipolytic, Gram-stain-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated GM-16T, was isolated from seawater around Pohang in the Republic of Korea. Strain GM-16T grew optimally at 30 °C and in the presence of 1.0-2.0% (w/v) NaCl. The neighbour-joining phylogenetic tree of 16S rRNA gene sequences showed that strain GM-16T fell within the clade comprising the type strains of Croceicoccus species. Strain GM-16T exhibited the highest 16S rRNA gene sequence similarity (97.7%) to the type strain of Croceicoccus pelagius and sequence similarities of 96.3-96.7% to the type strains of the other Croceicoccus species. Strain GM-16T contained Q-10 as the predominant ubiquinone and C18: 1ω7c and summed feature 3 (C16: 1ω7c and/or C16: 1ω6c) as major fatty acids. The major polar lipids of strain GM-16T were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid and one unidentified glycolipid. The DNA G+C content of strain GM-16T was 62.6 mol%. The mean DNA-DNA relatedness value between strain GM-16T and C. pelagius DSM 101479T was 16%. The average nucleotide identity values between strain GM-16T and the type strains of Croceicoccus pelagius, Croceicoccus marinus, Croceicoccus naphthovorans and Croceicoccus mobilis were 83.96-84.44%. The phylogenetic and genetic data and differential phenotypic properties indicated that strain GM-16T is separated from recognized Croceicoccus species. On the basis of the data presented here, strain GM-16T is considered to represent a novel species of the genus Croceicoccus, for which the name Croceicoccus ponticolasp. nov. is proposed. The type strain is GM-16T (=KACC 19611T=KCTC 62423T=NBRC 113192T).