Maribellus mangrovi sp. nov., an iron- reducing bacterium isolated from mangrove sediment

A novel facultatively anaerobic and Gram- stain- negative bacterium, designated FJH33T, was isolated from mangrove sediment sampled in Zhangzhou, PR China. Cells of strain FJH33T were rod- shaped or slightly curved- shaped, with widths of 0.3-0.5 mu m and lengths of 1.0-3.0 mu m. Optimum growth of strain FJH33T occurred in the presence of 3 % NaCl (w/v), at 33 degrees C and at pH 7.0. Oxidase activity was negative, while catalase activity was positive. Its iron- reducing ability was determined. Based on 16S rRNA gene sequence similarity, strain FJH33T was most closely related to Maribellus luteus XSD2T (95.1 %), followed by Maribellus sediminis Y2-1-60T (95.0 %) and Maribellus maritimus 5E3T (94.9 %). Genome analysis of strains FJH33T and M. luteus XSD2T revealed low genome relatedness, with an average nucleotide identity value of 73.8% and a digital DNA-DNA hybridization value of 19.0%. Phylogenetic trees built from 16S rRNA genes and genome sequences showed that strain FJH33T represents a relatively independent phylogenetic lineage within the genus Maribellus. The major cellular fatty acids (>= 10 %) were iso- C15: 0 and C18: 1 omega 9c. The sole respiratory quinone was MK- 7. The polar lipids consisted of phosphatidylethanolamine, diphosphatidylcholine, diphosphatidyglycerol and one unidentified lipid. The DNA G+C content was 41.4 mol%. Based on the integrated results of phylogenetic, physiological, biochemical and chemotaxonomic characterizations, we propose that strain FJH33T represents a novel species of the genus Maribellus, for which the name Maribellus mangrovi sp. nov. is proposed. The type strain is FJH33T (=KCTC 102210T=MCCC 1H01459T).