Marinomonas brasilensis sp. nov., isolated from the coral Mussismilia hispida, and reclassification of Marinomonas basaltis as a later heterotypic synonym of Marinomonas communis

Abstract

A Gram-negative, aerobic bacterium, designated strain R-40503(T), was isolated from mucus of the reef-builder coral Mussismilia hispida, located in the São Sebastião Channel, São Paulo, Brazil. Phylogenetic analyses revealed that strain R-40503(T) belongs to the genus Marinomonas. The 16S rRNA gene sequence similarity of R-40503(T) was above 97 % with the type strains of Marinomonas vaga, M. basaltis, M. communis and M. pontica, and below 97 % with type strains of the other Marinomonas species. Strain R-40503(T) showed less than 35 % DNA-DNA hybridization (DDH) with the type strains of the phylogenetically closest Marinomonas species, demonstrating that it should be classified into a novel species. Amplified fragment length polymorphism (AFLP), chemotaxonomic and phenotypic analyses provided further evidence for the proposal of a novel species. Concurrently, a close genomic relationship between M. basaltis and M. communis was observed. The type strains of these two species showed 78 % DDH and 63 % AFLP pattern similarity. Their phenotypic features were very similar, and their DNA G+C contents were identical (46.3 mol%). Collectively, these data demonstrate unambiguously that Marinomonas basaltis is a later heterotypic synonym of Marinomonas communis. Several phenotypic features can be used to discriminate between Marinomonas species. The novel strain R-40503(T) is clearly distinguishable from its neighbours. For instance, it shows oxidase and urease activity, utilizes l-asparagine and has the fatty acid C(12 : 1) 3-OH but lacks C(10 : 0) and C(12 : 0). The name Marinomonas brasilensis sp. nov. is proposed, with the type strain R-40503(T) ( = R-278(T) = LMG 25434(T) = CAIM 1459(T)). The DNA G+C content of strain R-40503(T) is 46.5 mol%.