一株乳酸菌产类细菌素Enteriocin LK-S1的初步研究

Preliminary Studies on Bacteriocin-like Substance Synthesized by Enterococcus

从鸡肠道分离的 5 9株乳酸菌中 ,筛选出一株产类细菌素的乳酸菌 ,编号为SE - 81.初步鉴定为肠球菌属 (Enterococcus) .在排除有机酸和过氧化氢的干扰作用后 ,SE - 81菌株对溶壁微球菌(Micrococcuslysodeikticus)、金黄色葡萄球菌 (Staphylococcusaureus)和枯草杆菌 (Bacillussubtilis)等革兰氏阳性菌和大肠杆菌 (Escherichiacoli)及鼠伤寒沙门氏菌 (Salmonellatyphimurium)等革兰氏阴性菌有强烈的抑制作用 .用胰蛋白酶处理发酵上清液后 ,抑菌活性丧失 .因此初步认为该菌株产生一类具有广谱抑菌活性的类细菌素物质 ,命名为EnteriocinLK -S1.它具有较广的抗菌谱 ,作用pH在 4 .0～ 6 .0 ,有很好的热稳定性 .

WT5'BZA strain, SE-81, produced inhibitory activity substance, was screened in 59 lactic acid bacteria isolated from intestine of the chicken by a dual-culture plate assay and identified as Enterococcus. The supernatant of Enterococcus SE-81 eliminated the organic acids and hydrogen peroxide exhibited strong inhibitory activity against the gram-positive bacteria, including WTBXMicrococcus lysodeikticus, Staphylococcus aureus and Bacillus subtilis. A strong activity was also observed against the gram-negative bacteria, such as WTBXEscherichia.coliWTBZ and WTBXSalmonella typhimurium.WTBZ The inhibitory activity was totally lost after treatment with trypsin. The protein nature and restricted spectrum of substance points to its being bacteriocin-like substance, termed as EneriocinLK-S1, which has the broad-spectrum antibacterial and very high heat stability, active range of pH (4.0～6.0).