%0 Journal Article %A 丛瑜 %A 林洪 %A 王静雪 %T Development of cationic peptide chimeric lysins based on polyvalent phage lysin and their antibacterial activities %D 2022 %R 10.13995/j.cnki.11-1802/ts.031476 %J Food and Fermentation Industries %P 1-6 %V 48 %N 20 %X Polyvalent phage vB_SEqdws-315 can lyse both Salmonella and Escherichia coli strains, which has the potential to be used as antibacterial agents. In order to further study the antibacterial effect of its endolysin Lysin315, the gene was cloned and expressed in Escherichia coli BL21(DE3) with the induction of IPTG. High-purity recombinant Lysin315 was obtained by affinity chromatography. The molecular weight of Lysin315 was close to 25 kDa. Lysin315 needed EDTA as membrane permeability agents to inhibit the gram-negative bacteria because of the limitation of the cell wall structure of gram-negative bacteria. In order to enhance the direct antibacterial activity, Lysin315 was modified by cationic peptides to obtain chimeric lysins (Lysin315-5aa, Lysin315-10aa and Lysin315-15aa). All of the recombinant lysins were cloned and expressed in E. coli BL21(DE3) induced by IPTG and purified by affinity chromatography to acquire high purity. The results showed that cationic lysins could independently inhibit the hosts with high concentration without any membrane permeabilities. Lysin315-10aa also showed good antibacterial activities against Salmonella (106 CFU/mL) in milk at 4°C and 25°C. The development of cationic peptide chimeric lysins provided a solution for the independent application of gram-negative bacteriophages lysins. %U http://sf1970.cnif.cn/EN/10.13995/j.cnki.11-1802/ts.031476