Abstract
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.
Highlights
Quality of life achieved by modern society would be im-possible without tremendous development of chemical industry within the past century
The presence of an organophosphorus hydrolase gene in the bacterial genome was assessed by PCR with forward and reverse primers derived from the sequence of the parathion hydrolase gene of Sphingobium fuliginis, accession number M29593 (Table 1) [30,31,32]
POXN01 nucleotide sequences were deposited in GenBank under the following accession numbers: KC189953, KC189954, KC 189955, KC189956, KC 189957, KC189958, KC189959, KC152 907, KC189960, KC189961 (16S rRNA gene fragment), KC189 962, KC189963, KC189964, KC189965
Summary
Possible without tremendous development of chemical industry within the past century. Organophosphorus (OP) compounds are of great concern considering their environmental impact and threat to human health These synthetic chemicals are potent cholinesterase inhibitors once intended for military use, but at the present time, widely employed as insecticides. There are risks associated with major international efforts to destroy the stockpiled chemical warfare agents [7] Despite their high toxicity, OP pesticides are extensively used in developing countries [8]. A strain that can simultaneously degrade multiple types of xenobiotics will be a preferable tool for decontamination of heavily polluted sites like landfills and sewage collectors It can be included in a variety of environmental clean-up scenarios as a multipurpose remedy for pollution. We describe characterization of this microorganism along with identification of molecular constituents responsible for its ability to detoxify xenobiotics
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
