Marinobacterium coralli sp. nov., isolated from mucus of coral (Mussismilia hispida)

Abstract

A Gram-negative, aerobic bacterium, designated R-40509T, was isolated from mucus of the reef builder coral (Mussismilia hispida) located in the São Sebastião Channel, São Paulo, Brazil. The strain was oxidase-positive and catalase-negative, and required Na+ for growth. Its phylogenetic position was in the genus Marinobacterium and the closest related species were Marinobacterium sediminicola, Marinobacterium maritimum and Marinobacterium stanieri; the isolate exhibited 16S rRNA gene sequence similarities of 97.5–98.0 % with the type strains of these species. 16S rRNA gene sequence similarities with other type strains of the genus Marinobacterium were below 96 %. DNA–DNA hybridizations between strain R-40509T and the type strains of the phylogenetically closest species of the genus Marinobacterium revealed less than 70 % DNA–DNA relatedness, supporting the novel species status of the strain. Phenotypic characterization revealed that the strain was able to grow at 15–42 °C and in medium containing up to 9 % NaCl. The isolate could be differentiated from phenotypically related species by several features, including its ability to utilize d-alanine, l-alanine, bromosuccinic acid, β-hydroxybutyric acid and α-ketovaleric acid, but not acetate or l-arabinose. It produced acetoin (Voges–Proskauer), but did not have esterase lipase (C8) or catalase activities. It possessed C18 : 1 ω7c (35 %), summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1 ω7c; 25 %) and C16 : 0 (22 %) as major cellular fatty acids. The DNA G+C content was 58.5 mol%. The name Marinobacterium coralli sp. nov. is proposed to accommodate this novel isolate; the type strain is R-40509T (=LMG 25435T =CAIM 1449T).