摘要
Bacteria contamination in Auricularia auricular culture bags reduces yield and increases the risk of food safety.In this study,5 species of bacteria,mainly gram-positive bacteria including three species of Bacillus spp.,Arthrobacter arilaitensis and Staphylococcus warneri,were isolated and identifi ed from bacteria-contaminated A.auricular culture bags.An in silico predicted antimicrobial peptide from theβ-1,3-glucan-binding protein sequence of Penaeus vannamei,designated Pv GBP2(FLKLGRKSRYGMLKL),was screened and its antibacterial effect and mechanism of action on the isolated Bacillus spp.explored.The minimal inhibitory concentrations(MIC)of Pv GBP2 on Bacillus spp.were 15.6–31.25μg/m L.Peptide Pv GBP2 could inhibit Bacillus subtilis in A.auricular culture bags to maintain growth and yield of A.auricular.Transmission electron microscopy(TEM)revealed that Pv GBP2 kills bacteria by perforating the cell wall,destroying membrane integrity and resulting in the leakage of intracellular solutes.In addition,Pv GBP2 inhibits biofi lm formation by B.subtilis by 90.6%at 1×MIC.Thus,peptide Pv GBP2 could be potentially applied as an antibacterial agent to control bacterial infection of A.auricular cultivation and the spread of foodborne pathogens.
基金
sponsored by National Key R&D Program of China(2020YFD09009)。