Process of a Photobacterial Cascade Reaction for Biobased Adipic Acid

Area of Science:

• Biotechnology and synthetic biology
• Green chemistry and sustainable processes
• Biocatalysis and photocatalysis

Background:

• Adipic acid is a key polymer monomer, vital for food packaging and industrial applications.
• Developing biobased adipic acid aligns with the "Dual Carbon" strategy for environmental sustainability.
• Existing l-lysine-based pathways face challenges with low catalytic activity and unidentified enzymes.

Purpose of the Study:

• To engineer a microbial strain for enhanced biosynthesis of l-2-aminoadipate, an adipic acid precursor.
• To develop a novel photocatalytic method for converting l-2-aminoadipate to adipic acid.
• To establish an integrated photomicrobial cascade system for sustainable adipic acid production.

Main Methods:

• Constructed the l-2-aminoadipate biosynthesis pathway in Corynebacterium glutamicum.
• Coexpressed specific dehydrogenases and optimized precursor gene expression for increased l-2-aminoadipate yield.
• Utilized treated rape pollen (TRP) as a photocatalyst for converting l-2-aminoadipate to adipic acid under light irradiation.

Main Results:

• Achieved 1.02 g/L of l-2-aminoadipate, a 6.4-fold increase compared to the parental strain.
• Successfully synthesized 235 mg/L of adipic acid via photocatalytic conversion in 48 hours.
• Demonstrated the efficacy of a photomicrobial cascade reaction system for chemical synthesis.

Conclusions:

• Developed a novel and efficient method for biobased adipic acid production using microbial fermentation and photocatalysis.
• The photomicrobial cascade approach offers a sustainable alternative, potentially replacing enzymatic conversions with unknown mechanisms.
• This strategy provides a new paradigm for synthesizing valuable chemicals through integrated biocatalytic and photocatalytic processes.