title: Adaptation of the autotrophic acetogen Sporomusa ovata to methanol accelerates the conversion of CO2 to organic products.
abstract: Acetogens are efficient microbial catalysts for bioprocesses converting C1 compounds into organic products. Here, an adaptive laboratory evolution approach was implemented to adapt Sporomusa ovata for faster autotrophic metabolism and CO2 conversion to organic chemicals. S. ovata was first adapted to grow quicker autotrophically with methanol, a toxic C1 compound, as the sole substrate. Better growth on different concentrations of methanol and with H2-CO2 indicated the adapted strain had a more efficient autotrophic metabolism and a higher tolerance to solvent. The growth rate on methanol was increased 5-fold. Furthermore, acetate production rate from CO2 with an electrode serving as the electron donor was increased 6.5-fold confirming that the acceleration of the autotrophic metabolism of the adapted strain is independent of the electron donor provided. Whole-genome sequencing, transcriptomic, and biochemical studies revealed that the molecular mechanisms responsible for the novel characteristics of the adapted strain were associated with the methanol oxidation pathway and the Wood-Ljungdahl pathway of acetogens along with biosynthetic pathways, cell wall components, and protein chaperones. The results demonstrate that an efficient strategy to increase rates of CO2 conversion in bioprocesses like microbial electrosynthesis is to evolve the microbial catalyst by adaptive laboratory evolution to optimize its autotrophic metabolism.
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Hørsholm, Denmark.
authors.forename: Pier-Luc
authors.initials: PL
authors.lastname: Tremblay
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Hørsholm, Denmark.
authors.forename: Daniel
authors.initials: D
authors.lastname: Höglund
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Hørsholm, Denmark.
authors.forename: Anna
authors.initials: A
authors.lastname: Koza
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Hørsholm, Denmark.
authors.forename: Ida
authors.initials: I
authors.lastname: Bonde
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Hørsholm, Denmark.
authors.forename: Tian
authors.initials: T
authors.lastname: Zhang
mesh_terms: D000085:Acetates / Q000378:metabolism; D000596:Amino Acids / Q000096:biosynthesis; D001426:Bacterial Proteins / Q000378:metabolism; D002245:Carbon Dioxide / Q000737:chemistry / Q000378:metabolism*; D004566:Electrodes; D000068536:Bacillota / Q000378:metabolism*; D000432:Methanol / Q000737:chemistry / Q000378:metabolism*; D018832:Molecular Chaperones / Q000378:metabolism; D010084:Oxidation-Reduction; D011743:Pyrimidines / Q000096:biosynthesis; D014815:Vitamins / Q000096:biosynthesis
chemical_list: D000085:Acetates; D000596:Amino Acids; D001426:Bacterial Proteins; D018832:Molecular Chaperones; D011743:Pyrimidines; D014815:Vitamins; D002245:Carbon Dioxide; D000432:Methanol