Antimicrobial Mechanism of Antimicrobial Peptide LL-1 Against Klebsiella pneumoniae ATCC 700603
[Objective]This experiment was aimed to study the antibacterial effect and mechanism of a novel antibacterial peptide LL-1.[Method]The minimum inhibitory concentration(MIC)of antibacterial peptide LL-1 against Klebsiella pneumoniae was detected,and the in vitro antibacterial effect of antibacterial peptide LL-1 against Klebsiella pneumoniae was evaluated through the antibacterial curve.Leakage of alkaline phosphatase(ALP),β-galactosidase,nucleic acid and protein were determined to evaluate the effect of antibacterial peptide LL-1 on the cell membrane and cell wall of Klebsiella pneumoniae.The binding of antibacterial peptide LL-1 to Klebsiella pneumoniae DNA was detected by nucleic acid gel electrophoresis.The effect of antibacterial peptide LL-1 on the morphology of Klebsiella pneumoniae was observed through scanning electron microscopy.[Result]Antibacterial peptide LL-1 had good antibacterial activity against Klebsiella pneumoniae,with a MIC of 50 μg/mL.The antibacterial curve showed that 2 MIC of antibacterial peptide LL-1 could completely inhibit the growth of Klebsiella pneumoniae within 6 h.Antibacterial peptide LL-1 led to the leakage of ALP and β-galactosidase of Klebsiella pneumoniae,and 1/4 MIC of antibacterial peptide LL-1 resulted in a extremely significantly higher leakage rate than the control group(P＜0.01).The detection of nucleic acid and protein leakage further confirmed that antibacterial peptide LL-1 might cause the efflux of intracellular contents in Klebsiella pneumoniae.In addition,antibacterial peptide LL-1 could bind to the DNA of Klebsiella pneumoniae.The results of scanning electron microscope observation suggested that antibacterial peptide LL-1 caused the surface of Klebsiella pneumoniae to become rough,bacterial deformation.[Conclusion]The results showed that antibacterial peptide LL-1 increased the permeability of the cell wall and membrane in Klebsiella pneumoniae,and bound with the DNA of Klebsiella pneumoniae,and thus exerted antibacterial effects.This would lay the foundation for in-depth research on the antibacterial mechanism of antibacterial peptide LL-1 against Klebsiella pneumoniae.
国家科技期刊平台
NSTL
万方数据
维普
