Food-grade gene transformation system constructed in Lactobacillus plantarum using a GlmS-encoding selection marker. Issue 21 (11th October 2018) - Chen, Ying
Abstract: 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 P ldhL 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. Abstract : Using glmS gene as a selection marker replaces antibiotic-resistant markers to construct a food-grade expression system in Lactobacillus plantarum .