Description of Comamonas sediminis sp. nov., isolated from lagoon sediments.

Strain S3T was isolated from lagoon sediments, and appeared as transparent colonies on agar plates, with cells staining Gram-negative. Catalase and oxidase were positive. S3T hydrolyzed starch, casein and tween-20, while urea, chitin, gelatin and tween-80 were not hydrolysed. C18 : 1ω6c/C18 : 1ω7c, C16 : 1ω6c/C16 : 1ω7c,C17 : 0 cyclo and C16 : 0 were the predominant fatty acids with minor amounts of C10 : 0 3-OH, C12 : 0, C14 : 0 and C16 : 0 2-OH. S3T contained diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), and phosphatidylethanolamine (PE) as major polar lipids with minor amounts of unidentified phospholipid (PL) and unidentified lipids (L1-2). Genomic DNA G+C content was 68.3 mol%. 16S rRNA gene sequence comparisons indicated that S3T represents a member of the genus Comamonas in family Comamonadaceae of the class Betaproteobacteria. S3T has a sequence similarity of 98.96 % with Comamonas koreensis YH12T, 97.93 % with Comamonas guangdongensis CY01T and <96.97 % with other members of the genus Comamonas. DNA-DNA hybridization values between S3T and the type strains of the most closely related species were clearly below the 70 % threshold. On the basis of phenotypic, genotypic and phylogenetic analysis, it is proposed that S3T represents a novel species of the genus Comamonas, for which the name Comamonas sediminis sp. nov. is proposed. The type strain is S3T (=KEMB 563-466T =JCM 31169T).