Metabolic and genetic factors affecting the productivity of @entity35343 in XXXX .

@entity7682 @entity35343 @entity3183 @entity5537 @entity3881 @entity6683
BACKGROUND: @entity3183 and @entity6683 are produced commercially by @entity3881 . The production strains of @entity3183 and @entity6683 were both derivatives from mutagenesis. However, the exact metabolic and genetic factors affecting the productivity remain unknown. Genetic engineering may be a promising approach to identify and confirm these factors. RESULTS: With the deletion of the cdd and hom genes, and the deregulation of the pyr operon in @entity7682 , the engineered strain produced 200.9  mg/L @entity3183 , 14.9  mg/L @entity6683 and 960.1  mg/L @entity5537 . Then, the overexpressed prs gene led to a dramatic increase of @entity6683 by 25.9 times along with a modest increase of @entity3183 . Furthermore, the overexpressed pyrG gene improved the production of @entity3183 , @entity6683 and @entity5537 by 259.5%, 11.2% and 68.8%, respectively. Moreover, the overexpression of the pyrH gene increasesd the yield of @entity3183 by 40%, along with a modest augments of @entity6683 and @entity5537 . Lastly, the deletion of the nupC-pdp gene resulted in a doubled production of @entity6683 up to 1684.6  mg/L, a 14.4% increase of @entity3183 to 1423  mg/L, and a 99% decrease of @entity5537 to only 14.2  mg/L. CONCLUSIONS: The deregulation of the pyr operon and the overexpression of the prs, pyrG and pyrH genes all contribute to the accumulation of @entity35343 compounds in the medium. Among these factors, the overexpression of the pyrG and pyrH genes can particularly facilitate the production of @entity3183 . Meanwhile, the deletion of the nupC-pdp gene can obviously reduce the production of @entity5537 and simultaneously improve the production of @entity6683 .
