title: Selective loss of lin genes from hexachlorocyclohexane-degrading Pseudomonas aeruginosa ITRC-5 under different growth conditions.
abstract: The chlorinated insecticide gamma-hexachlorocyclohexane (gamma-HCH) is sequentially metabolized by the products of linA, linB, linC, linD, linE, and linF genes to beta-ketoadipate, which is subsequently mineralized. Two or more copies of these genes are present in the bacterium Pseudomonas aeruginosa ITRC-5 that was isolated earlier by selective enrichment on technical-HCH. At least one copy of linA, linB, linC, linD, and possibly linE is lost from ITRC-5 upon its growth on gamma-HCH. All the lin genes, however, are lost when the bacterium was grown in Luria-Bertani (LB) medium. The loss of lin genes is accompanied with the loss/rearrangement of insertion sequence IS6100 genes. Concomitant to the loss of lin genes, the degradation of HCH-isomers by "gamma-HCH grown cells" is slower, when compared with "technical-HCH grown cells", and is completely lost by "LB-grown cells". The selective loss of lin genes during different growth conditions has not been reported before and is expected to help in understanding the dynamism of degradative genes.
authors.affiliation: Environmental Biotechnology Section, Industrial Toxicology Research Center, Mahatma Gandhi Marg, Lucknow, 226001, India.
authors.forename: Atul K
authors.initials: AK
authors.lastname: Singh
authors.forename: Pankaj
authors.initials: P
authors.lastname: Chaudhary
authors.forename: Ankit S
authors.initials: AS
authors.lastname: Macwan
authors.forename: Upendra N
authors.initials: UN
authors.lastname: Diwedi
authors.forename: Ashwani
authors.initials: A
authors.lastname: Kumar
mesh_terms: D001483:Base Sequence; D001673:Biodegradation, Environmental; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D001556:Hexachlorocyclohexane / Q000378:metabolism*; D007306:Insecticides / Q000378:metabolism*; D008190:Lyases / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000737:chemistry / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D007306:Insecticides; D012336:RNA, Ribosomal, 16S; D001556:Hexachlorocyclohexane; D008190:Lyases; C019994:dehydrochlorinases