Abstract: Objective we got a lot of recombinant human α-defensin-3 by genetic engineering method, and studied whether to increase ciprofloxacin antibiotic activity to resistant strains of Pseudomonas aeruginosa. Method RT-PCR retroviral human blood leukocytes of the total RNA, and PCR amplification of the target gene, cloned into pET32a (+) plasmid. Transformed into the recombinant E. coli and the affinity chromatography purified protein. By calculating HNP-3 and ciprofloxacin MIC value and FIC detection of recombinant protein biological activity. Results Construction of a pET32a (+) / HNP-3 original expression vector, and the expression of protein was determined the purpose of protein. The FIC value of combination of HNP-3 and ciprofloxacin is less than 1.0. Conclusion human α-defensin-3 enhanced ciprofloxacin antibiotic activity to resistant strains of Pseudomonas aeruginosa.

Key words: Human neutrophil peptide, Gene recombination, Pseudomonas aeruginosa., FIC