Abstract:Hexachlorocyclohexane (HCH) has been used extensively against agricultural pests and in public health programs for the control of mosquitoes. Commercial formulations of HCH consist of a mixture of four isomers, ␣, , ␥, and ␦. While all these isomers pose serious environmental problems, -HCH is more problematic due to its longer persistence in the environment. We have studied the degradation of HCH isomers by Sphingomonas paucimobilis strain B90 and characterized the lin genes encoding enzymes from strain B90… Show more
“…In another example i.e. lindane [18], endosulfan [19,20], DDT [21] and monocrotophos [22,23], the microbes and/or enzymes were isolated and identifi ed. Genetic studies of microbial degradation indicates that the plasmids are the main place for the gene of interest usually spread throughout the microbial community.…”
Section: Recent Developments In Pesticide Biodegradationmentioning
Biodegradation is a natural process, where the degradation of a xenobiotic chemical or pesticide by an organism is primarily a strategy for their own survival. Most of these microbes work in natural environment but some modifi cations can be brought about to encourage the organisms to degrade the pesticide at a faster rate in a limited time frame. This capability of microbe is some times utilized as technology for removal of contaminant from actual site. Knowledge of physiology, biochemistry and genetics of the desired microbe may further enhance the microbial process to achieve bioremediation with precision and with limited or no scope for uncertainty and variability in microbe functioning. Gene encoding for enzyme has been identifi ed for several pesticides, which will provide a new inputs in understanding the microbial capability to degrade a pesticide and develop a super strain to achieve the desired result of bioremediation in a short time.
“…In another example i.e. lindane [18], endosulfan [19,20], DDT [21] and monocrotophos [22,23], the microbes and/or enzymes were isolated and identifi ed. Genetic studies of microbial degradation indicates that the plasmids are the main place for the gene of interest usually spread throughout the microbial community.…”
Section: Recent Developments In Pesticide Biodegradationmentioning
Biodegradation is a natural process, where the degradation of a xenobiotic chemical or pesticide by an organism is primarily a strategy for their own survival. Most of these microbes work in natural environment but some modifi cations can be brought about to encourage the organisms to degrade the pesticide at a faster rate in a limited time frame. This capability of microbe is some times utilized as technology for removal of contaminant from actual site. Knowledge of physiology, biochemistry and genetics of the desired microbe may further enhance the microbial process to achieve bioremediation with precision and with limited or no scope for uncertainty and variability in microbe functioning. Gene encoding for enzyme has been identifi ed for several pesticides, which will provide a new inputs in understanding the microbial capability to degrade a pesticide and develop a super strain to achieve the desired result of bioremediation in a short time.
“…All these sphingomonads have similar lin genes for HCH degradation. S. indicum B90A, S. francense Sp+ and S. japonicum UT26 have similar linA, linB, linC, linD, linE, linR and linF genes for γ-HCH degradation [8,46]. The rate of HCH degradation in S. francense Sp+ is similar to S. japonicum UT26 but all HCH isomers are degraded much more effi ciently by S. indicum B90A.…”
Section: Distribution Of Lin Genes Among Hch Degrading Bacteriamentioning
confidence: 97%
“…Sphingomonas paucimobilis B90A was found to contain two copies of linA gene [46]. A thorough analysis of two copies of linA revealed 88% amino acids similarity between them.…”
Section: Unfolding Of Hch Degradation Pathway and Lin Genes In Sphingmentioning
confidence: 99%
“…The C-terminal region of one of the linA gene in B90A was found to be replaced by 22 nucleotides of adjoining IS6100 element [8]. The two copies were named as linA1 and linA2 and while linA1 was found only in S. paucimobilis B90A, linA2 was 100% identical to that of S. paucimobilis UT26 and S. paucimobilis Sp+ [46]. Cloning and expression of these two gene revealed that linA1 re- tained the dehydrochlorinase activity even with the 22-nucleotide variation.…”
Section: Unfolding Of Hch Degradation Pathway and Lin Genes In Sphingmentioning
confidence: 99%
“…Although purifi ed preparation of LinB of strain UT26 transformed β-HCH to PCCH, crude cell incubation with strain UT26 had no affect on β-HCH transformation [60]. However, this was in contrast to B90A that was repeatedly found to degrade β-HCH [7,8,46,61]. This prompted us to look into the degradation of β-HCH by using purifi ed LinB of B90A as well as whole cell preparation of Sphingobium indicum B90A [62].…”
Section: Evolution Of Lin Genes To Perform Newer Function In B90amentioning
The unusual process of production of hexachlorocyclohexane (HCH) and extensive use of technical HCH and lindane has created a very serious problem of HCH contamination. While the use of technical HCH and lindane has been banned all over the world, India still continues producing lindane. Bacteria, especially Sphingomonads have been isolated that can degrade HCH isomers. Among all the bacterial strains isolated so far, Sphingobium indicum B90A that was isolated form HCH treated rhizosphere soil appears to have a better potential for HCH degradation. This conclusion is based on studies on the organization of lin genes and degradation ability of B90A. This strain perhaps can be used for HCH decontamination through bioaugmentation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.