Three water-borne bacterial isolates were collected from the Houston metropolitan area. Each isolate was capable of growing upon carbon limited media inoculated with the organophosphorus (OP) compound paraoxon. All is...Three water-borne bacterial isolates were collected from the Houston metropolitan area. Each isolate was capable of growing upon carbon limited media inoculated with the organophosphorus (OP) compound paraoxon. All isolates were able to efficiently metabolize paraoxon and, to a lesser degree, methyl parathion to p-nitrophenol. 16S rDNA genome sequencing with universal bacterial primers identified the isolates as species belonging to the genera Aeromonas, Steno- trophomonas, or Exiguobacterium. All screened isolates harbor organophosphorus degradation (opd) genes that are approximately 99% similar over approximately 660 base pairs sequenced to one first isolated from Sphingobium fuliginis ATCC 27551 (formerly Flavobacterium sp. ATCC 27551). Additionally, two isolates KKWT11, identified as a putative Senotro- phomonas maltophilia, and KKBO11, identified as a putative Exiguobacterium indicum, were found to possess genomic DNA that closely matched a metallo- beta-lactamase that has been reported to function as a methyl parathion degradation (mpd) gene suggesting that both of these strains are prime candidates for wastewater remediation of a broad range of OP compounds.展开更多
A bacterial strain designated in this study as POXN01 was found to be capable of degrading the synthetic organophosphorus pesticides paraoxon and methyl parathion. The strain was initially isolated through enrichment ...A bacterial strain designated in this study as POXN01 was found to be capable of degrading the synthetic organophosphorus pesticides paraoxon and methyl parathion. The strain was initially isolated through enrichment technique from rice field soil near Harlingen, Texas. Phylogenetic analysis based on 16S rRNA, gyrB and rpoD gene alignments identified the POXN01 isolate as a new strain of Pseudomonas putida, which is closely related to the recently discovered nicotine-degrading strain Pseudomonas putida S16. While being unable to metabolize nicotine, the POXN01 isolate was observed to actively proliferate using monocyclic aromatic hydrocarbons, in particular toluene, as nutrients. Search for the genetic determinants of paraoxon catabolism revealed the presence of organophosphorus-degrading gene, opd, identical to the one from Sphingobium fuliginis (former Flavobacterium sp. ATCC 27551). Assimilation of aromatic compounds likely relies on phc ARKLMNOPQ gene cluster for phenol, benzene and toluene catabolism, and on benRABCDKGEF cluster for benzoate catabolism. The observed versatility of POXN01 strain in degradation of xenobiotics makes it useful for the multi-purpose bioremediation of contaminated sites in both agricultural and industrial environmental settings.展开更多
文摘Three water-borne bacterial isolates were collected from the Houston metropolitan area. Each isolate was capable of growing upon carbon limited media inoculated with the organophosphorus (OP) compound paraoxon. All isolates were able to efficiently metabolize paraoxon and, to a lesser degree, methyl parathion to p-nitrophenol. 16S rDNA genome sequencing with universal bacterial primers identified the isolates as species belonging to the genera Aeromonas, Steno- trophomonas, or Exiguobacterium. All screened isolates harbor organophosphorus degradation (opd) genes that are approximately 99% similar over approximately 660 base pairs sequenced to one first isolated from Sphingobium fuliginis ATCC 27551 (formerly Flavobacterium sp. ATCC 27551). Additionally, two isolates KKWT11, identified as a putative Senotro- phomonas maltophilia, and KKBO11, identified as a putative Exiguobacterium indicum, were found to possess genomic DNA that closely matched a metallo- beta-lactamase that has been reported to function as a methyl parathion degradation (mpd) gene suggesting that both of these strains are prime candidates for wastewater remediation of a broad range of OP compounds.
文摘A bacterial strain designated in this study as POXN01 was found to be capable of degrading the synthetic organophosphorus pesticides paraoxon and methyl parathion. The strain was initially isolated through enrichment technique from rice field soil near Harlingen, Texas. Phylogenetic analysis based on 16S rRNA, gyrB and rpoD gene alignments identified the POXN01 isolate as a new strain of Pseudomonas putida, which is closely related to the recently discovered nicotine-degrading strain Pseudomonas putida S16. While being unable to metabolize nicotine, the POXN01 isolate was observed to actively proliferate using monocyclic aromatic hydrocarbons, in particular toluene, as nutrients. Search for the genetic determinants of paraoxon catabolism revealed the presence of organophosphorus-degrading gene, opd, identical to the one from Sphingobium fuliginis (former Flavobacterium sp. ATCC 27551). Assimilation of aromatic compounds likely relies on phc ARKLMNOPQ gene cluster for phenol, benzene and toluene catabolism, and on benRABCDKGEF cluster for benzoate catabolism. The observed versatility of POXN01 strain in degradation of xenobiotics makes it useful for the multi-purpose bioremediation of contaminated sites in both agricultural and industrial environmental settings.
