Engineered strain and the construction method and use thereof

Abstract

An engineered strain for improving tryptophan production and a construction method and use thereof are provided. By screening out a strain capable of tolerating high-concentration tryptophan and performing genomic sequencing and protein sequence analysis on the strain, it is found that certain proteins in the strain undergo point mutations and these mutations are capable of enhancing tryptophan production. To increase tryptophan production, protein sequences encoded by fadR or pepD genes in a parent strain are modified. These modifications result in an engineered strain with significantly higher tryptophan production compared to the parent strain. Under scaled-up production conditions, the tryptophan production reaches 62.38±5.80 g/L in a 5 L fermenter, with a glucose-to-tryptophan yield of 24.1%. Compared to an original strain, tryptophan production increases by 1.48-fold, and the glucose-to-tryptophan yield improves by 1.26-fold. The biological materials and its use belong to the technical field of molecular biology and possess broad practical application value.

Dependencies are inferred from the claim text.