Digestive Stability of AM79 EPSPS Protein in Simulative Gastric and Intestinal Fluid

doi:10.13560/j.cnki.biotech.bull.1985.2017-0072

Abstract

Abstract: AM79 EPSPS is a novel glyphosate-resistant gene with independent intellectual property rights in China and isolated from highly glyphosate-polluted soil using metagenomics method. The gene owns a promising value because its overexpression in the transgenic corn increased the corns’ glyphosate resistances. In order to evaluate the safety of AM79 EPSPS protein as food,the digestive stability of AM79 EPSPS protein in simulative gastric and intestinal fluid was analyzed according to the national standard of the People’s Republic of China. Gene AM79 EPSPS was constructed into prokaryotic expression vector pET-30a,and the soluble AM79 EPSPS protein of 48.3 kD was expressed in Escherichia coli,and purified using Ni-NTA chromatography. The digestive stability of the purified AM79 EPSPS protein was performed via in vitro simulative gastric and intestinal fluid. The results showed that the AM79 EPSPS protein was completely digested within 15 s in the simulated gastric and intestinal fluid,no any remain of protein was detected by SDS-PAGE and Western blotting,indicating that AM79 EPSPS protein was easily digested in the simulated gastric and intestinal fluid.

Key words: AM79 EPSPS protein, glyphosate, simulative gastric and intestinal fluid, digestive stability

WANG Yu, WANG Jian-hua, LIU Yun-jun. Digestive Stability of AM79 EPSPS Protein in Simulative Gastric and Intestinal Fluid[J]. Biotechnology Bulletin, 2017, 33(6): 176-181.

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