Systematic design and evaluation of artificial CO₂ assimilation pathways.

Area of Science:

• Metabolic Engineering and Synthetic Biology
• Biotechnology and Bio-agriculture
• Computational Biology and Bioinformatics

Background:

• Effective management of carbon dioxide (CO2) is crucial due to industrial and bio-agricultural advancements.
• Developing efficient artificial carbon fixation pathways is a significant challenge for humanity.

Purpose of the Study:

• To systematically explore CO2 assimilation pathways using the comb-FBA algorithm.
• To identify efficient artificial carbon fixation pathways for industrial and bio-agricultural applications.

Main Methods:

• Construction of a computational set by extracting 49 CO2 and HCO3- involved reactions and integrating them with 6,529 reactions from MetaCyc.
• Utilized the comb-FBA algorithm to analyze 16 core reactions, generating 136 pathways for C2 targets and 576 pathways for C3 targets.
• Assessed enzyme oxygen sensitivity, availability, and metabolite conversion relationships to identify promising pathways and modules.

Main Results:

• Identified four principal carbon fixation modes and 12 thermodynamically feasible CO2 fixation pathways with a maximum of 20 reaction steps.
• Discovered three novel and promising artificial carbon fixation pathways after analyzing enzyme properties.
• Identified alternative carbon fixation reaction modules, enhancing flexibility for pathway optimization.

Conclusions:

• The study provides a diverse library of artificial carbon fixation pathways.
• The comb-FBA algorithm demonstrates significant power in designing novel carbon assimilation pathways.
• This research lays the foundation for developing more efficient CO2 fixation strategies.