Abstract: The present invention provides a mutant strain of Corynebacterium glutamicum with efficient expression of exogenous proteins, which can solve the technical problem of low protein expression quantity of using Corynebacterium glutamicum as an exogenous protein expression host. The mutant strain of Corynebacterium glutamicum is deposited in the China General Microbiological Culture Collection Center (CGMCC), and the deposit number is CGMCC No. 20138. The mutant strain of Corynebacterium glutamicum in the present invention, verified by the expression of exogenous proteins, shows a significantly enhanced expression of both intracellular and secreted proteins when compared with its initial strain.

Abstract: The present invention relates to a method for constructing a recombinant bacterium with high production of ?-elemene and germacrene A. Firstly, ?-elemene and germacrene A are synthesized from scratch through the screening of germacrene A synthase and the overexpression of the mevalonate pathway; then, the availability of acetyl-CoA, pyruvate, and glyceraldehyde-3-phosphate in the farnesyl diphosphate pathway is ensured by deleting competing pathways in the central carbon metabolism; next, the present invention uses lycopene color as a high-throughput screening method and obtains an optimized NSY305N through error-prone PCR. Finally, in shake flasks, strain ?-EL-4 constructed through key pathway enzymes, efflux engineering, and translation engineering produced 1161.09 mg/L of ?-elemene and 852.36 mg/L of germacrene A, which is the highest reported yield at shake flask level. In 4-L fed-batch fermentation, the production of ?-elemene and germacrene A reached 3.52 g/L and 2.13 g/L, respectively.

Abstract: The present invention provides a mutant strain of Corynebacterium glutamicum with efficient expression of exogenous proteins, which can solve the technical problem of low protein expression quantity when existing Corynebacterium glutamicum is used as an exogenous protein expression host. The mutant strain of Corynebacterium glutamicum is deposited in the China General Microbiological Culture Collection Center (CGMCC), and the deposit number is CGMCC No. 20138. The mutant strain of Corynebacterium glutamicum in the present invention, verified by the expression of exogenous proteins, showed significantly enhanced expression of both intracellular and secreted proteins when compared with its initial strain.