Granulosicoccus marinus sp. nov., isolated from Antarctic seawater, and emended description of the genus Granulosicoccus

Abstract

A Gram-staining-negative, motile by flagella, non-pigmented, poly-β-hydroxybutyrate-producing, strictly aerobic and sphere-shaped bacterium, IMCC3490T, was isolated from a coastal seawater sample from the Antarctic Peninsula. Optimal growth of strain IMCC3490T was observed at 20 °C, pH 8.0 and in the presence of 2 % (w/v) NaCl. Phylogenetic analysis using 16S rRNA gene sequences indicated that strain IMCC3490T belonged to the genus Granulosicoccus in the family Granulosicoccaceae . The strain was closely related to Granulosicoccus antarcticus IMCC3135T (98.8 % 16S rRNA gene sequence similarity) and Granulosicoccus coccoides Z 271T (98.5 %). The DNA–DNA relatedness values between IMCC3490T and type strains of the two species of the genus were far lower than 70 %, which indicated strain IMCC3490T is a novel genomic species of the genus Granulosicoccus . The major fatty acids of strain IMCC3490T were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The isoprenoid quinone detected was ubiquinone-8 (Q-8) and predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The DNA G+C content was 61.0 mol%. On the basis of phylogenetic analyses, DNA–DNA relatedness values and phenotypic data, it is suggested that strain IMCC3490T represents a novel species of the genus Granulosicoccus , for which the name Granulosicoccus marinus sp. nov. is proposed. The type strain is IMCC3490T ( = KACC 17483T = NBRC 109704T). An emended description of the genus Granulosicoccus is also provided.