Recombinant Expression,Purification And Activity Of Two Antimicrobial Peptide Cgmolluscidin And Padef

Antibacterial peptide(Antimicrioal peptide)can kill the microbiology directly or act on the defense systems of numerous organisms toward multiple pathogens such as bacteria,fungi,parasites and viruses without the risk of drug resistance.They have become extremely significant due to the increasing resistance of microorganisms to common antibiotics.However,the isolation of peptides directly from natural sources sometimes is time consuming,environmental unfriendly,high-cost strategy.This study focuses on the related strategies for achieving high-production levels of functional peptides.In this study we express two antimicrobial peptide using two different expression system separately.The prokaryotic expression system represented by E.coli to express a novel antimicrioal peptide cgMolluscidin which comes from the Pacific oyster with recombinant vector pET28a-cgMolluscidin and pGEX-cgMolluscidin,the yield of fusion cgMolluscidin reached 8.5 g/L and 12.1 g/L respectively after expression and purification.The eukaryotic expression system represented by pichia pastoris to express a novel antimicrobial peptide PaDef with the recombinant vector pPICZaA-PaDef,the yield of PaDef was about 158 mg/L after expression and purification.The the antimicrobial peptide cgMolluscidin using E.coli expression system does not appear obvious bacteriostatic activity,while the PaDef using Pichia Pastoris expression system shows obvious activity in gram-positive bacteria staphylococcus aureus ATCC 25923,bacillus subtilis and listeria monocytogenes ATCC 21633,and the minium inhibition concentration to staphylococcus aureus ATCC 25923 reached about 19 ?g/ml.The results show that the pichia pastoris system has certain feasibility to produce antibacterial peptides,and the products may be applied in the pharmaceutical industry as well as in additives,cosmetics.