Marinomonas blandensis sp. nov., a novel marine gammaproteobacterium

A novel Gram-staining-negative, chemoorganotrophic, moderately halophilic, strictly aerobic bacterium, strain MED121T, was isolated from a seawater sample collected at the Blanes Bay Microbial Observatory in the north-western Mediterranean Sea. Analysis of its 16S rRNA gene sequence, retrieved from the whole-genome sequence, showed that this bacterium was most closely related to Marinomonas dokdonensis and other Marinomonas species (96.3 and 93.3-95.7 % sequence similarities, respectively), within the family Oceanospirillaceae. Strain MED121T was included into a whole-genome sequencing study and, subsequently, it was characterized using a polyphasic taxonomic approach. It was found to be oxidase and catalase positive, its cells are cocci to short rods, it does not ferment carbohydrates and does not reduce nitrate to nitrite or gas and it requires at least 2.5 % (w/v) marine salts and tolerates up to 7 % (w/v) salts. Its major cellular fatty acids in order of abundance are C16 : 1ω7c/C16 : 1ω6c, C18 : 1ω7c, C16 : 0 and C10 : 0 3-OH. Its genome had an approximate length of 5.1 million bases and a DNA G+C content equal to 40.9 mol%. Analysis of the annotated genes reveals the capacity for the synthesis of ubiquinone 8 (Q8) and the polar lipids phosphatidylglycerol and phosphatidylethanolamine, in agreement with other members of the genus. All the data collected supported the creation of a novel species to accommodate this bacterium, for which the name Marinomonas blandensis sp. nov. is proposed. The type strain is MED121T (=CECT 7076T=LMG 29722T).