Algibacillus agarilyticus gen. nov., sp. nov., isolated from the surface of the red algae Gelidium amansii

Abstract

A novel Gram-stain-negative, strictly aerobic, coccoid and agar-hydrolysing bacterium, designated RQJ05^T, was isolated from the marine red algae Gelidium amansii collected from the coastal area of Rizhao, PR China. Cells of strain RQJ05^T were approximately 0.8-1.0×1.3-3.0 µm in size and motile by means of a polar flagellum. Growth occurred at 4-33 °C (optimum, 25-30 °C), pH 7.0-8.5 (optimum, pH 7.5-8.0) and in the presence of 1.0-7.0 % (w/v) NaCl (optimum, 2.0-3.0 %). Strain RQJ05^T showed oxidase-positive and catalase-negative activities. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain RQJ05^T formed a phylogenetic lineage with members of the family Alteromonadaceae and exhibited 16S rRNA gene sequence similarities of 92.6, 91.3, 90.2 and 90.1 % to Catenovulum maritimum Q1^T, Catenovulum agarivorans YM01^T, Paraphotobacterium marinum NSCS20N07D^T and Algicola sagamiensis B-10-31^T, respectively. The major cellular fatty acids of strain RQJ05^T were summed feature 3 (C_{16 : 1} ω7c and/or C_{16 : 1} ω6c), C_{16 : 0} and summed feature 8 (C_{18 : 1} ω7c and/or C_{18 : 1} ω6c). The major polar lipids of strain RQJ05^T were phosphatidylethanolamine, phosphatidylglycerol and two aminophospholipids. Strain RQJ05^T contained Q-8 as the major respiratory quinone. The genomic DNA G+C content was 39.0 mol%. On the basis of genotypic, phenotypic and phylogenetic evidence, strain RQJ05^T is presented as a representative of a novel species in a new genus, for which the name Algibacillus agarilyticus gen. nov., sp. nov. is proposed. The type strain is RQJ05^T (=KCTC 62846^T=MCCC 1H00352^T).

Keywords: Alteromonadaceae; draft genome; phylogenetic analysis.