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

Abstract

IntroductionFlavobacterium sp. ATCC 27551 was isolated from paddy fi eld water of the Philippines as a degrader of organophosphorus pesticides such as diazinon and parathion (Sethunathan and Yoshida, 1973a). The pesticides were found to be degraded by organophosphorus hydrolase (Mulbry and Karns, 1989) which was encoded on a 43-kb plasmid (Mulbry et al., 1986). The organophosphorus hydrolase has a broad range of substrates and functions at broad pH and temperature (Mulbry et al., 1986), and therefore considered to be useful for the detoxifi cation of the pesticide-polluted environment. Moreover, it has been recently applied to the degradation of nerve agents such as sarin and soman (Dumas et al., 1990) for decontamination in the case of chemical terrorism.In spite of the intensive study of the degrading enzyme, classifi cation of the producer of the enzyme has not attracted attention, and strain ATCC 27551 has been kept as Flavobacterium sp. since the early studies of this bacterium in 1970s (Sethunathan and Yoshida, 1973b). However, bacterial taxonomy has developed in these several decades and the members of the genus Flavobacterium have been reclassifi ed to other taxa.Sphingomonas was fi rst proposed by Yabuuchi et al. (1990) with fi ve species, but later developed to large group of species, and the new family Sphin- J. Gen. Appl. Microbiol., 56, 249 255 (2010) A parathione-degrading bacterium isolated from rice fi eld 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 ω7c), 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 identifi ed as S. fuliginis.

Characterization of polyhydroxyalkanoates (PHAs) biosynthesis by isolatedNovosphingobiumsp. THA_AIK7 using crude glycerol

“…The purification procedure might be improved in order to remove more impurities by using depyrogenating agents such as NaOH, hydrogen peroxide, and supercritical CO 2 [22,40]. In our study, the negative result of endotoxin in the THA_AIK7 polymer product at a sensitivity of 0.25 EU ml -1 by gel-clot formation could be preliminarily assessed as the absence of bacterial endotoxin in agreement with the data of LPS lacking, which were obtained by Takeuchi et al [32] and Kawahara et al [19]. This could verify that the polymer produced by Novosphingobium sp.…”

“…This genus was divided into 4 clusters, Sphingomonas, Sphingobium, Novosphingobium, and Sphingopyxis, on the basis of their 16S rRNA gene sequence and by combining the phylogenetic, chemotaxonomic, and phenotypic data by Takeuchi et al [32]. One characteristic of the species of genus Sphingomonas is, unlike common gram-negative bacteria, the presence of glycosphingolipids (GSLs) as the cell envelope component instead of lipopolysaccharide (LPS) [19,32].…”

Isolation and molecular characterization of a novel <i>pseudomonas putida</i> strain capable of degrading organophosphate and aromatic compounds

“…Previous reports have identified several organophosphate-degrading bacterial species, among them are Sphingobium fuliginis (former Flavobacterium sp. ATCC 27551) [15,16] and Brevundimonas diminuta GM (former Pseudomonas diminuta GM) [17,18], both express-ing identical organophosphate hydrolase enzymes. Organophosphate hydrolase is a zinc-containing homodimeric membrane protein that has been found to hydrolyze paraoxon at a rate approaching the diffusion limit [19].…”

Aminoalcohol-Induced Activation of Organophosphorus Hydrolase (OPH) towards Diisopropylfluorophosphate (DFP)

“…ATCC 27551, recently identified as Sphingobium fuliginis [30], was obtained from the American Type Culture Collection (Manassas, VA, USA) for the opd gene cloning. The E .…”