Two-dimensional isobutyl acetate production pathways to improve carbon yield

Area of Science:

• Biochemical Engineering
• Metabolic Engineering
• Synthetic Biology

Background:

• High carbon yield is critical for economically competitive biological production processes.
• Pyruvate decarboxylation during acetyl-CoA formation from sugars limits theoretical maximum carbon yield (TMCY) and can cause redox imbalance.
• Current methods using single carbon sources like sugar have inherent limitations in efficiency.

Purpose of the Study:

• To develop a metabolic pathway that overcomes the limitations of single-substrate utilization.
• To enable simultaneous utilization of glucose and acetate for producing acetyl-CoA without carbon loss or redox imbalance.
• To enhance the production of target chemicals like isobutyl acetate (IBA).

Main Methods:

• Construction of a novel metabolic pathway for dual carbon source utilization (glucose and acetate).
• Engineering the pathway to produce acetyl-CoA from acetate, avoiding carbon release and redox issues.
• Demonstration of the pathway's efficacy using isobutyl acetate (IBA) as a target chemical.

Main Results:

• The dual-substrate pathway successfully utilized both glucose and acetate.
• Isobutyl acetate (IBA) production using glucose and acetate achieved a higher carbon yield compared to using either sole carbon source.
• The approach effectively avoids carbon loss and redox imbalance associated with traditional pyruvate decarboxylation.

Conclusions:

• Simultaneous utilization of multiple carbon sources, like glucose and acetate, offers a viable strategy to improve theoretical maximum carbon yield (TMCY).
• This approach enhances redox balance in biosynthetic pathways.
• The developed metabolic pathway holds significant potential for more efficient and sustainable biochemical production.