Marinobacterium maritimum sp. nov., a marine bacterium isolated from Arctic sediment.

A Gram-negative, aerobic, rod-shaped, motile, marine bacterium, strain AR11(T), was isolated from Arctic marine sediment. Strain AR11(T) grew with 0.5-7 % NaCl and at 7-37 degrees C and pH 5.5-9.0. It utilized propionate, 3-hydroxybenzoate, l-proline, acetate, d- and l-lactate, l-alanine, malate and phenylacetic acid. Alkaline phosphatase, esterase lipase (C8), leucine arylamidase and acid phosphatase activity tests were positive. Acid was produced from 5-ketogluconate and aesculin. Strain AR11(T) possessed C(16 : 0) (22.0 %), summed feature 4 (C(16 : 1)omega7c and/or iso-C(15 : 0) 2-OH; 28.1 %) and summed feature 7 (one or more of C(18 : 1)omega7c, omega9t and omega12t; 34.0 %) as the major cellular fatty acids. The major ubiquinone was Q-8. Comparative 16S rRNA gene sequence studies showed that strain AR11(T) belonged to the Gammaproteobacteria and was most closely related to Marinobacterium stanieri DSM 7027(T), Marinobacterium halophilum mano11(T) and Marinobacterium georgiense KW-40(T) (97.8, 97.0 and 96.7 % similarity, respectively). The G+C content of the genomic DNA of strain AR11(T) was 57.9 mol%. DNA-DNA relatedness data indicated that strain AR11(T) represented a distinct species that was separated from M. stanieri DSM 7027(T), M. halophilum KCTC 12240(T) and M. georgiense JCM 21667(T). On the basis of evidence from this polyphasic study, it is proposed that strain AR11(T) (=KCTC 22254(T)=JCM 15134(T)) represents the type strain of a novel species, Marinobacterium maritimum sp. nov.