Mechanism of action of vitamin K.
We have discovered a novel, spontaneous model oxidation that leads to a powerful base capable of carrying out a carbon-carbon bond forming condensation reaction analogous to that observed in the vitamin K-mediated carboxylation of glutamate. The model sequence incorporates a novel base-strength enhancement sequence and it implicates molecular oxygen as the initiating factor in the vitamin K-dependent carboxylation. When the oxygenation is carried out under an atmosphere of (18)O2, two atoms of (18)O are incorporated into the vitamin K oxide product. Selective (18)O labelling defines the carbonyl group next to methyl as the active site of the vitamin K.
Dowd
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Department of Chemistry, University of Pittsburgh, PA 15260, USA.
Hershline
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Ham
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Naganathan
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D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects / Q000502:physiology; D002118:Calcium / Q000378:metabolism; D006528:Carcinoma, Hepatocellular / Q000737:chemistry; D006801:Humans; D008958:Models, Molecular; D015394:Molecular Structure; D014812:Vitamin K / Q000737:chemistry / Q000493:pharmacokinetics* / Q000502:physiology
D014812:Vitamin K; D002118:Calcium