植物乳杆菌WUH3细菌素合成基因分析及其特性研究

Analysis of bacteriocin synthesis gene and bacteriocin properties of Lactobacillus plantarum WUH3

植物乳杆菌WUH3(Lactobacillus plantarum WUH3)是从中国传统腌制黄瓜中分离得到的1株具有良好抑菌活性的乳酸菌。该文通过对L.plantarum WUH3进行基因分析和试验验证来探明其性质和应用价值。首先,该文对L.plantarum WUH3进行了全基因组测序,从基因层面分析其潜在特性,结果显示,该菌株含有与细菌素合成相关的多种转运蛋白基因,以及3种细菌素:Plantaricin_EF、Pediocin和Enterocin_X_chain_beta,表明该菌株具有细菌素的合成分泌能力。一系列验证试验结果表明,该菌株可分泌蛋白质类细菌素,其分子质量为4.1~6.5 kDa,具有良好的热稳定性(121℃,30 min)和pH稳定性(pH 2~11)。进一步研究结果表明,该细菌素对多种腐败菌和致病菌有抑制作用,具备广谱抑菌性;其通过作用于细菌的细胞膜表面,致使其细胞膜破裂,从而发挥抑菌性能。最后,该文对L.plantarum WUH3进行安全性分析,发现其为非人类致病菌,可被应用于食品防腐领域。该研究为L.plantarum WUH3的开发和应用提供了一定的参考价值。

Lactobacillus plantarum WUH3 was a lactic acid bacterium isolated from Chinese traditional pickled cucumber,which has good antibacterial activity.In this paper,the properties and application value of L.plantarum WUH3 were studied by gene analysis and experimental verification.Firstly,the whole genome of L.plantarum WUH3 was sequenced and analyzed to predict its properties.Results showed that this strain contained many transporter genes related to bacteriocin synthesis,and three bacteriocins synthesis genes:Plantarin_EF,Pediocin and Enterocin_X_chain_beta,indicating that the strain had the ability to synthesize and secrete bacteriocin.A series of experiments were designed to show that this strain could secrete bacteriocin with the molecular weight between 4.1-6.5 kDa.Its bacteriocin had good thermal stability(121℃,30 min)and pH stability(pH 2-11).Further research showed that this bacteriocin could inhibit a variety of spoilage bacteria and pathogens,which proved it has a broad-spectrum antibacterial activity.Especially,the bacteriocin exerted its antibacterial effect by acting on the surface of cell membrane and causing membranolysis.Finally,we analyzed the safety of L.plantarum WUH3,and found that it was harmless to human body.Thus,it can be used for food preservation.This study is useful for the development and application of L.plantarum WUH3.