Comparing the protein characteristics and antibacterial activity of antibacterial peptide FALL-39 and its mutant peptides

OBJECTIVE To compare the protein characteristics of antibacterial peptide FALL-39 and its mutant peptides.METHODS Using AU-PAGE elution,HPLC and omiga analysis software,the protein characteristics of purified peptides of FALL-39 and its mutant peptides,FALL-39-Lys32,FALL-39-Lys24 and FALL-39-Lys24′32 were analyzed.MEC,MIC and MBC were used to assay the antibacterial activities of these peptides.The antibacterial assay showed that mutant peptides were more potent in the antibacterial activity against E.coli ATCC 25922,E.coli ML 35p and Pseudomonas aeruginosa ATCC 27853 than that of FALL-39.RESULTS FALL-39 mutants peptides ran faster than FALL-39 in AU-PAGE elution,while the retention time of HPLC.Hydrophobicity,protein flexibility and von heijne transmembrane helices did not change.CONCLUSION FALL-39 mutant peptides have increasing antibacterial activity and net positive charge,but with no protein characteristics change.