title: Indirect observation by 13C NMR spectroscopy of a novel CO2 fixation pathway in methanogens.
abstract: High-field carbon-13 nuclear magnetic resonance (NMR) spectroscopy has been used to monitor the isotopic dilution of doubly carbon-13-labeled precursors for 2,3-cyclopyrophosphoglycerate, a novel primary metabolite that occurs in certain methanogens. A unique carbon dioxide fixation pathway that gives rise to asymmetric labeling of acetyl coenzyme A has been demonstrated in Methanobacterium thermoautotrophicum. The effect of selected metabolic inhibitors on the labeled species in the pathway has been examined by NMR. These techniques establish a general, sensitive method for the delineation of convergent biosynthetic pathways.
authors.forename: J N
authors.initials: JN
authors.lastname: Evans
authors.forename: C J
authors.initials: CJ
authors.lastname: Tolman
authors.forename: M F
authors.initials: MF
authors.lastname: Roberts
mesh_terms: D000085:Acetates / Q000378:metabolism; D002245:Carbon Dioxide / Q000378:metabolism*; D002247:Carbon Isotopes; D019605:Euryarchaeota / Q000254:growth & development / Q000378:metabolism*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D011773:Pyruvates / Q000378:metabolism
chemical_list: D000085:Acetates; D002247:Carbon Isotopes; D011773:Pyruvates; D002245:Carbon Dioxide