Reclassification of a parathione-degrading Flavobacterium sp. ATCC 27551 as Sphingobium fuliginis

Abstract

A parathione-degrading bacterium isolated from rice field in the Philippines, Flavobacterium sp. ATCC 27551 (Sethunathan and Yoshida, 1973, Can. J. Microbiol., 19, 873-875), was re-examined chemotaxonomically and phylogenetically. The strain contained 2-hydroxymyristic acid (2-OH 14 : 0), cis-vaccenic acid (18 : 1 omega7c), and palmitic acid (16 : 0) as major cellular fatty acids, two kinds of glycosphingolipids, and ubiquinone-10 as a sole quinone component. The G+C content of genomic DNA of the strain was 65.9 mol%. The phylogenetic analyses of the 16S rRNA gene indicated that the strain was included in the family Sphingomonadaceae, and most closely related to Sphingobium fuliginis (98.0% similarity) and Sphingobium herbicidovorans (97.3%). The strain showed similar physiological characteristics and a moderate value of DNA-DNA relatedness to S. fuliginis. These data suggested it reasonable to conclude that strain ATCC 27551 was identified as S. fuliginis.