designing a new recombinant strain with additional copy number of dsz cluster to enhance biodesulfurization activity in pseudomonas aeruginosa atcc 9027

the combustion of sulfur-rich fossil fuels leads to the release of acid rain-causing sulfurdioxide into the environment. the aim of this study was to enhance the efficiency of biodesulfurizationusing pseudomonas aeruginosa through the duplication of the dsz cluster in this organism. one copy ofthe dsz cluster was inserted by a tri-parental mating method into the chromosome of pseudomonasaeruginosa atcc 9027 strain, and another copy in the form of a plasmid was cloned under control of atac promoter. the recombinant pseudomonas sp. was able to desulfurize dibenzothiophene moreefficiently than the strains which contain only one copy of dsz cluster. efficiency of dibenzothiophene(dbt) desulfurisation was measured through the release of 2-hidroxybiphenyle (2-hpb).this is the firsttime that an increase in desulfurisation activity through gene duplication has been shown.