title: Enhanced desulfurization in a transposon-mutant strain of Rhodococcus erythropolis.
abstract: The dsz desulfurization gene cluster from Rhodococcus erythropolis strain KA2-5-1 was transferred into R. erythropolis strain MC1109, unable to desulfurize light gas oil (LGO), using a transposon-transposase complex. As a result, two recombinant strains, named MC0203 and MC0122, were isolated. Resting cells of strain MC0203 decreased the sulfur concentration of LGO from 120 mg l(-1) to 70 mg l(-1) in 2 h. The LGO-desulfurization activity of strain MC0203 was about twice that of strain MC0122 and KA2-5-1. The 10-methyl fatty acids of strain MC0203 were about 28%-41% that of strain MC1109. It is likely that strain MC0203 had a mutation involving alkylenation or methylation of delta9-unsaturated fatty acids caused by the transposon inserted in the chromosome, which increased the fluidity of cell membranes and enhanced the desulfurization activity.
mesh_terms: D001711:Biotransformation; D004251:DNA Transposable Elements / Q000235:genetics*; D005648:Fuel Oils; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D018014:Gene Transfer Techniques; D024861:Genetic Enhancement / Q000379:methods*; D009154:Mutation; D010105:Oxygenases / Q000235:genetics* / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D012240:Rhodococcus / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D013045:Species Specificity; D013455:Sulfur / Q000378:metabolism*; D013876:Thiophenes / Q000378:metabolism*
chemical_list: D004251:DNA Transposable Elements; D005648:Fuel Oils; D011994:Recombinant Proteins; D013876:Thiophenes; D013455:Sulfur; D010105:Oxygenases; C016366:dibenzothiophene