The effect on shikimate production by deleting iolR and metabolic engineering in PTS deficient Corynebacterium glutamicum strain

TL;DR

This study improves shikimate production in a modified Corynebacterium glutamicum strain by deleting iolR and using metabolic engineering.

Contribution

The novel approach combines iolR deletion and metabolic engineering in a PTS-deficient strain to enhance shikimate production.

Findings

Deleting iolR improved cell growth and shikimate production in the PTS-deficient strain.

Overexpressing glycolysis and shikimate pathway genes further increased shikimate output.

The engineered strain achieved a shikimate titer of 4.1 g/L in shake flask cultures.

Abstract

Shikimate is a precursor to many high-value chemical derivatives. Several bacteria have been engineered to produce high titer of shikimate via non-phosphotransferase system (Non-PTS), but yet explores how the myo-inositol utilization transcription regulator (iolR) deletion affects the shikimate titer in phosphotransferase system (PTS) deficient strain. In this study, we engineered Corynebacterium glutamicum to produce shikimate in a PTS deficient strain with the deletion of iolR and improved shikimate production using a metabolic engineering approach. PTS was eliminated to improve phosphoenolpyruvate levels, however, both the cell growth rate and shikimate production were dramatically reduced. Hence, iolR was deleted to improve cell growth and shikimate production in the PTS deficient strain. In addition, we overexpressed genes in the glycolysis and shikimate pathways to increase shikimate production. The combination of the strategies resulted in a shikimate content of 0.76 mg/mg of DCW and a titer of 4.1 g/L in shake flask in C. glutamicum, providing novel insights for further engineering to enhance production of shikimate and its derivatives.

Figures