Construction of prokaryotic expressing vector of antisense nucleic acid of lasR and its effect on the virulence of Pseudomonas aeruginosus.

To construct a pUCP18/lasR(antisense) plasmid carrying the reversed gene and analyze its effect on the virulence of Pseudomonas aeruginosus, LasR gene was amplified from the genome of Pseudomonas aeruginosus by PCR and reversely recombined with plasmid pUCP18. The recombinant pUCP18/lasR (antisense) was verified by enzyme digestion, PCR and sequencing. The biological effects of pUCP18/lasR (antisense) were examined by using RT-PCR, NAD method and the assay of pyocyanin. Our results showed that the expected full length lasR fragment (721 bp) was extended from Pseudomonas aeruginosus gene with PCR. And it is consistent with LasR gene of Pseudomonas aeruginosa in GenBank (No. NC_002516). The recombinant plasmid was successfully constructed and transferred into Pseudomonas aeruginosus. The antisense nucleic acid of LasR gene could reduce the virulence of Pseudomonas aeruginosus and might serve as a new target site for treatment purpose.