The active species of "CO2" utilized in ferredoxin-linked carboxylation reactions.
The active species of "CO2", i.e. CO2 or HCO-3(H2CO3) utilized by enzymes catalyzing ferredoxin-linked carboxylation reactions was determined. The enzyme investigated was pyruvate synthase from Clostridium pasteurianum (EC 1.2.7.1; Pyruvate: ferredoxin oxidoreductase). Data were obtained which were compatible with those expected if CO2 is the active species. The dissociation constant (Ks) of the enzyme-CO2 complex was measured. At pH 7.2 Ks for CO2 of pyruvate synthase was found to be approximately 5 mM.
D000105:Acetyl Coenzyme A / Q000378:metabolism; D001639:Bicarbonates / Q000378:metabolism; D002245:Carbon Dioxide / Q000378:metabolism*; D002255:Carbonic Acid / Q000378:metabolism; D003013:Clostridium / Q000201:enzymology*; D005288:Ferredoxins / Q000378:metabolism*; D007658:Ketone Oxidoreductases / Q000378:metabolism*; D007700:Kinetics; D011773:Pyruvates; D013835:Thiamine Pyrophosphate / Q000378:metabolism
D001639:Bicarbonates; D005288:Ferredoxins; D011773:Pyruvates; D002245:Carbon Dioxide; D002255:Carbonic Acid; D000105:Acetyl Coenzyme A; D007658:Ketone Oxidoreductases; D013835:Thiamine Pyrophosphate