title: Recycling of carbon dioxide and acetate as lactic acid by the hydrogen-producing bacterium Thermotoga neapolitana.
abstract: The heterotrophic bacterium Thermotoga neapolitana produces hydrogen by fermentation of sugars. Under capnophilic (carbon dioxide requiring) conditions, the process is preferentially associated with the production of lactic acid, which, as shown herein, is synthesized by reductive carboxylation of acetyl coenzyme A. The enzymatic coupling is dependent on the carbon dioxide stimulated activity of heterotetrameric pyruvate:ferredoxin oxidoreductase. Under the same culture conditions, T. neapolitana also operates the unfavorable synthesis of lactic acid from an exogenous acetate supply. This process, which requires carbon dioxide (or carbonate) and an unknown electron donor, allows for the conversion of carbon dioxide into added-value chemicals without biomass deconstruction.
authors.affiliation: Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, Via Campi Flegrei 34, 80078 Pozzuoli-Napoli (Italy).
authors.forename: Giuliana
authors.initials: G
authors.lastname: d'Ippolito
authors.forename: Laura
authors.initials: L
authors.lastname: Dipasquale
authors.forename: Angelo
authors.initials: A
authors.lastname: Fontana
mesh_terms: D000085:Acetates / Q000378:metabolism*; D002245:Carbon Dioxide / Q000378:metabolism*; D004579:Electron Transport; D006859:Hydrogen / Q000378:metabolism*; D019344:Lactic Acid / Q000096:biosynthesis*; D059027:Recycling / Q000379:methods*; D046949:Thermotoga neapolitana / Q000378:metabolism*
chemical_list: D000085:Acetates; D002245:Carbon Dioxide; D019344:Lactic Acid; D006859:Hydrogen
keywords: carbon dioxide fixation; fermentation; hydrogen; isotopic labeling; metabolism