重组粪肠球菌gshF基因对副干酪乳杆菌(Lactobacillus paracasei)L14抗逆性能的影响

Introducing gshF into Lactobacillus paracasei L14 to Influence Its Stress Risistance Ability

乳酸菌作为重要的食品工业微生物,其在工业生产应用过程中会受到多种非生物胁迫。已有研究表明部分乳酸菌可以吸收培养基中或是自身合成谷胱甘肽(Glutathione,GSH),提高对各种胁迫的抵抗作用。克隆了粪肠球菌(Enterococcus faecalis)中的谷胱甘肽合成酶基因gshF,通过构建乳杆菌重组表达质粒,实现了gshF在副干酪乳杆菌(Lactobacillus paracasei)L14菌株中的异源表达。通过对重组gshF-副干酪乳杆菌阳性菌株的抗逆性性测定,结果表明在过氧化氢、酸、冻干脱水和渗透等胁迫条件下,gshF重组菌株的存活率与对照菌株相比均有显著提高。

As one of the important groups of food industry microorganisms, lactic acid bacteria will confront to various abiotic stresses when applied in industry. Previous studies suggested that some lactic acid bacteria can synthesize or absorb glutathione from the medium and protect themselves from diverse stress. In this study, glutathione synthetase gshF from Enterococcus faecalis, which can catalyze the synthesis of glutathione, was cloned and transformed into Lactobacillus paracasei L14 by Lactobacillus recombinant expression vector. The stresses resistance ability of the gshF recombinant strain was evaluated under stress conditions of hydrogen peroxide, acid, freeze-dry dehydration and osmosis. The results suggested that the survival rate of the gshF recombinant strain was greatly improved compare with the control strain.