Modular pathway engineering for enhanced production of -aminobenzoic acid and 4-amino-phenylalanine in via glucose/xylose co-utilization.

UNLABELLED

The modularization of biosynthetic pathways is a promising approach for enhancing microbial chemical production. We have developed a co-utilization method with glucose and xylose substrates to divide metabolic pathways into distinct production and energy modules to enhance the biosynthesis of -aminobenzoic acid (pABA) in . Optimizing initial glucose/xylose concentrations and eliminating carbon leakage resulted in a pABA titer of 8.22 g/L (yield: 0.23 g/g glucose). This strategy was then applied to the biosynthesis of 4APhe, a compound synthesized from chorismate without pyruvate (PYR) release. Utilizing glucose and xylose as co-substrates resulted in the production of 4.90 g/L 4APhe. Although 4APhe production did not benefit from PYR-driven energy generation as pABA production did, high titer was still achieved. This study highlights the effectiveness of modular metabolic pathway division for enhancing the production of key aromatic compounds and provides valuable insight into microbial production of chemicals that require specific biosynthetic donors such as amino groups.

IMPORTANCE

Microbial biosynthesis of chemicals from renewable resources offers a sustainable alternative to fossil fuel-based production. However, inefficiencies due to substrate diversion into by-products and biomass hinder optimal yields. In this study, we employed a modular metabolic engineering approach, decoupling pathways for chemical production from cell growth. Using glucose and xylose as co-substrates, we achieved the enhancement of -aminobenzoic acid production in . Additionally, we demonstrated the versatility of this approach by applying it to the biosynthesis of 4-amino-phenylalanine production. This study highlights the potential of modular metabolic pathway division for increased production of target compounds and provides valuable insight into microbial production of chemicals that require specific biosynthetic donors such as amino groups.