Marinicauda algicola sp nov., isolated from a marine red alga Rhodosorus marinus

Abstract

An aerobic Gram-stain-negative prosthecate bacterium, designated RMAR8-3(T), was isolated from a marine red alga Rhodosorus marinus in the Republic of Korea. Cells were dimorphic rods with a single polar prostheca (non-motile) or flagellum (motile) showing catalase-and oxidase-positive reactions. Growth of strain RMAR8-3(T) was observed at 15-45 degrees C (optimum, 40 degrees C), at pH 6.0-9.0 (optimum, pH 7.0) and in the presence of 0-10% (w/v) NaCl (optimum, 2 %). Ubiquinone-10 was detected as the sole isoprenoid quinone and C-18 : 0, summed feature 8 (comprising C-18 : 1 omega 7c and/or C-18 : 1 omega 6c), C-17 : 0, C-12 : 0 3-OH and C-16 : 0 were identified as the major cellular fatty acids. The major polar lipids were sulfoquinovosyldiacylglycerol, glucuronopyranosyldiglyceride and monoglycosyldiglyceride. The G+C content of the genomic DNA was 66.3 mol%. Strain RMAR8-3(T) was most closely related to Marinicauda pacifica P-1 km-3(T) with a 97.6% 16S rRNA gene sequence similarity. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain RMAR8-3(T) formed a tight phylogenic lineage with M. pacifica P-1 km-3(T) within the family Hyphomonadaceae. On the basis of phenotypic, chemotaxonomic and molecular features, strain RMAR8-3(T) clearly represents a novel species of the genus Marinicauda, for which the name Marinicauda algicola sp. nov. is proposed. The type strain is RMAR8-3 (T)(=KACC 18990(T)=JCM 31718(T)).