Department of Food Science and Technology, Jinling College, Nanjing Normal University, Nanjing 210097, China.
Institute of Animal Science, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China.
FEMS Microbiol Lett. 2018 Nov 1;365(21). doi: 10.1093/femsle/fny254.
Food-grade gene expression systems in lactic acid bacteria enable production of functional proteins or product testing without antibiotic requirement. Here, we expanded the available selection markers by developing a novel food-grade genetic transformation system for Lactobacillus plantarum WCFS1 using the glucosamine-6-phosphate synthase gene (glmS1). A glmS-vector pSIPH497 was constructed by replacing the erythromycin resistance gene (erm) with L. plantarum glmS1 under control of the PldhL promoter from WCFS1. The selection efficiency and stability of the glmS-vector were shown to be comparable to those of the erm-based plasmid. Moreover, using mCherry expression as a reporter gene, we showed the feasibility of the system for producing foreign proteins. This food-grade host/vector system will provide an effective and safe technique for the application of lactic acid bacteria in the food and medical industries. Furthermore, this study provides a useful strategy for developing food-grade selection markers in other host/vector systems.
在乳酸菌中使用食品级基因表达系统可以在无需抗生素的情况下生产功能性蛋白质或进行产品测试。在这里，我们通过利用葡萄糖胺-6-磷酸合酶基因（glmS1）为植物乳杆菌 WCFS1 开发了一种新型的食品级遗传转化系统，从而扩展了可用的选择标记。通过用来自 WCFS1 的 PldhL 启动子替换 erm 抗性基因（erm），构建了 glmS 载体 pSIPH497。glmS-载体的选择效率和稳定性与 erm 质粒相当。此外，我们使用 mCherry 表达作为报告基因，表明了该系统生产外源蛋白的可行性。这种食品级宿主/载体系统将为乳酸菌在食品和医疗行业的应用提供一种有效且安全的技术。此外，本研究为在其他宿主/载体系统中开发食品级选择标记提供了一种有用的策略。
