泡菜源植物乳杆菌HY41产细菌素性质及其基因簇挖掘

Characteristics of bacteriocin produced by Lactobacillus plantarum HY41 from pickles and its gene cluster mining

植物乳杆菌是食品生产中常用益生菌和发酵剂之一,在改善肠道菌群、维持肠道微环境平衡、增强胃肠消化吸收等方面具有重要作用。植物乳杆菌所产细菌素是天然防腐剂,具有应用价值。研究旨在进一步探究产细菌素植物乳杆菌HY41(GenBank序列号:OK355401.1)潜在适用性和安全性。发现该菌株在酸碱、热、紫外照射和有机溶剂作用下仍保持较高抑菌活性,可被蛋白酶K、木瓜蛋白酶以及碱性蛋白酶完全灭活,证明其为蛋白类物质,生物安全性良好。菌株HY41具有广谱抑菌特性且细菌素分子质量在3.3~5.8 ku。全基因组测序结果表明,菌株HY41基因组长度为2473086 bp,基因组平均GC含量46.02%。不存在抗生素抗性基因和毒力基因,存在两种Ⅱ类细菌素Pediocin PA和Pediocin基因。基因编码产物均为亲水蛋白,二级结构均以α-螺旋为主,三级结构与Pediocin PA-1 M31L和Ped B晶体结构最为接近。综上,通过挖掘植物乳杆菌HY41所产细菌素性质及其细菌素基因,证明植物乳杆菌HY41是一株具有潜在适用性和安全性的天然生物防腐培养物。

Lactobacillus plantarum is one of the most commonly used probiotics and starters in food production,and plays a significant role in improving intestinal flora,maintaining the balance of intestinal micro-environment,and enhancing gastrointestinal digestion and absorption.Bacteriocin produced by Lactobacillus plantarum were natural preservatives and had application values.The aim of this study was to further investigate the potential applicability and safety of bacteriocin-producing Lactobacillus plantarum HY41(nos.:OK355401.1).The strain was found to maintain high antibacterial activity under the action of acid,heat,UV irradiation and organic solvents,and could be completely inactivated by proteinase K,papain and alkaline protease,proving that it was a protein-like substance with good biosafety.The strain HY41 had broad-spectrum bacterial inhibitory properties and the molecular weight of bacteriocin ranges from 3.3 ku to 5.8 ku.The whole genome sequencing results showed that the genome size of strain HY41 was 2473086 bp and the GC content of the genome was 46.02%.There were no antibiotic resistance genes and virulence genes,and two class II bacteriocins genes(Pediocin PA and Pediocin)were present.The gene encoding products were all hydrophilic proteins,and the secondary structures were mainlyα-helix,and the tertiary structures were closest to the Pediocin PA-1 M31L and Ped B crystal structures.In conclusion,by analyzing the characteristics of bacteriocin produced by L.plantarum HY41 and mining its bacteriocin genes,it was demonstrated that L.plantarum HY41 was a natural biological preservative culture with potential applicability and safety.