To investigate the role and mechanism of defensin from rabbit neutrophils against pseudomonas aeruginosa and its drug-resistance strains.METHOD: Defensin was extracted from rabbit peritoneal neutrophil granules with citric acid, and purified by preparative acid urea polyacrylamide gel electrophoresis(AU-PAGE). In order to investigate the role andmechanism of defensins again pseudomonas aeruginosa and its cefetaxime-resistentance strain, We use an agrose gel radial diffusion assay for bactericidal activity in vitro and examined their ultrastructural changes by transmission electron microscope.
NP2 was isolated and puried successfully by AU-PAGE. NP2 demonstrated concentration-dependent killing of pseudomonas aeruginosa and its cefetaxime-resistentance strain. When the two kinds of Pseudomonas aeruginosa cells exposed to NP2 were examined by transmission electron microscope, we found that components in cells contracted high density balls and vacuolization.
Acid urea polyacrylamide gel electrophoresis is simple and convient in isolating and purifying protein and polypeptides. Defensin from rabbit neutrophils exerts potent bactericidal activity against pseudomonas aeruginosa and its cefetaxime resistance strain. The findings of electron microscope support the theory that defensins are capable of destabilizing the cell membrane permeability and causing the death of microorganism.CLINICAL IMPLICATION: Supplying the laboratory evidence for developing the nature antibiotic aganist MDR bacteria for the future.
B. Dong, None.