Acetogen and acetogenesis for biological syngas valorization

Area of Science:

• Biotechnology and Industrial Microbiology
• Chemical Engineering
• Synthetic Biology

Background:

• Syngas bioconversion by (homo)acetogens presents a promising alternative to thermochemical methods due to higher selectivity and milder conditions.
• Current processes excel in midstream engineering and downstream purification (TRLs), but upstream biocatalyst limitations hinder economic viability.
• The Wood-Ljungdahl pathway (WLP) is central to biological syngas utilization, involving complex redox balance and ATP generation.

Purpose of the Study:

• To review the Wood-Ljungdahl pathway for syngas bioconversion.
• To explore strategies for enhancing biocatalytic options in the upstream phase.
• To identify future directions for industrial syngas fermentation and valorization.

Main Methods:

• Focus on the Wood-Ljungdahl pathway (WLP) mechanism, including redox balance and ATP generation.
• Review of specific biocatalysts, such as Eubacterium limosum, for syngas valorization.
• Analysis of strategies for producing highly reduced chemicals, including flux control, mixed cultivation, and mixotrophy.

Main Results:

• Eubacterium limosum and other specific biocatalysts show potential for advantageous syngas valorization.
• Strategies like flux control, mixed cultivation, and mixotrophy can be employed to favor the production of highly reduced chemicals.
• The WLP provides a robust framework for microbial syngas conversion.

Conclusions:

• Optimizing upstream biocatalysis is key to improving the economic feasibility of syngas bioconversion.
• Targeted use of specific microorganisms and cultivation strategies can enhance the production of valuable chemicals from syngas.
• Further research into industrial syngas fermentation holds significant potential for sustainable chemical production.