Phycicoccus endophyticus sp. nov., an endophytic actinobacterium isolated from Bruguiera gymnorhiza

A novel endophytic actinobacterium, designated strain IP6SC6 T , was isolated from surface-sterilized bark of Bruguiera gymnorhiza collected from Zhanjiang Mangrove Forest National Nature Reserve in Guangdong, China. Cells of strain IP6SC6 T were Gram-stain-positive, aerobic, non-spore-forming, non-motile rods. Strain IP6SC6 T grew at 20-42 °C (optimum, 37 °C), at pH 6.0-9.0 (optimum, pH 7.0) and in the presence of 0-8 % (w/v) NaCl (optimum, 0-2 %). Chemotaxonomic analyses showed that the isolate possessed meso -diaminopimelic acid as the diamino acid of the peptidoglycan, galactose and glucose as whole-cell sugars, and MK-8(H 4 ) as the predominant menaquinone. The major polar lipids were diphosphatidylglycerol, phosphatidylinositol and an unknown lipid. The major fatty acids were iso-C 15 : 0 , anteiso-C 15 : 0 , anteiso-C 17 : 0 and iso-C 16 : 0 . The G+C content of the genomic DNA was 72.5 mol%. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain IP6SC6 T belonged to the genus Phycicoccus and shared the highest sequence similarity with Phycicoccus jejuensis NRRL B-24460 T (96.97 %). On the basis of phylogenetic analysis and phenotypic and chemotaxonomic characteristics, strain IP6SC6 T represents a novel species of the genus Phycicoccus , for which the name Phycicoccus endophyticus sp. nov. is proposed. The type strain is IP6SC6 T ( = DSM 100020 T  = CGMCC 4.7300 T ).