Pseudoalteromonas qingdaonensis sp. nov., isolated from the intestines of Ilyoplax deschampsi.

A Gram-stain-negative, aerobic, motile, catalase-positive, oxidase-positive, short rod-shaped marine bacterium, designated as YIC-827^T, was isolated from Qingdao, Shandong Province, China. The results showed that cells of strain YIC-827^T could grow optimally at 25-35 °C, pH 6.5-7.5 and 2-7% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence showed that the strain YIC-827^T was a member of the genus Pseudoalteromonas. The closest relative to this strain was Pseudoalteromonas ruthenica KMM 300^T, with a similarity of 98.39%. The digital DNA-DNA hybridization value between the new isolate and phylogenetically related species is 19.6%. Strain YIC-827^T could decompose sodium alginate, casein and esters (Tween 20, Tween 40, Tween 60 and Tween 80), but could not hydrolyse starch, cellulose and DNA. The fatty acid profile of a strain consists of a large number of C_16:0, C_18:1 ω7c and C_16:1 ω7c/_C16:1 ω6c. The G+C content of the DNA of this strain was determined to be 48.93%. Based on phenotypic characteristics, phylogenetic analysis and DNA-DNA correlation data, the strain YIC-827 ^T represents a novel species of the genus Pseudoalteromonas with the name Pseudoalteromonas qingdaonensis sp. nov. The type strain of P. qingdaonensis sp. is strain YIC-827^T (=MCCC 1K08807^T=CGMCC 1.62085^T=KCTC 8212^T).