Sandbox 212: Difference between revisions
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==Catalytic Mechanism of Carnitine Acyltransferases== | ==Catalytic Mechanism of Carnitine Acyltransferases== | ||
[[Image:Mechanism fatty acid transfer.jpg|thumb|700px|left]] | [[Image:Mechanism fatty acid transfer.jpg|thumb|catalytic mechanism of fatty acid transfer|700px|left]] | ||
It is assumed that the whole family of carnitine acyltransferases share the same catalytic mechanism, because certain residues in the catalytic side (histidine343, serine554) are conserved throughout the family. | It is assumed that the whole family of carnitine acyltransferases share the same catalytic mechanism, because certain residues in the catalytic side (histidine343, serine554) are conserved throughout the family. | ||
Histidine 343 is probably the most important residue in catalysis. First, it induces optimal substrate binding by forming a hydrogen bond between its side chain and the hydrogen atom of the substrate’s reactive group. As soon as all substrates attained the right position, the catalytic histidine residue is ready to extract a proton from either the hydroxyl group of carnitine or the thiol group of CoA. The catalytic histidine residue can be considered as a general base in catalysis.Which proton is extracted depends on the direction of the reaction. Acyl- carnitine is formed by extracting a proton from carnitine, whereas acyl-CoA is formed by extracting a proton from CoA. | Histidine 343 is probably the most important residue in catalysis. First, it induces optimal substrate binding by forming a hydrogen bond between its side chain and the hydrogen atom of the substrate’s reactive group. As soon as all substrates attained the right position, the catalytic histidine residue is ready to extract a proton from either the hydroxyl group of carnitine or the thiol group of CoA. The catalytic histidine residue can be considered as a general base in catalysis.Which proton is extracted depends on the direction of the reaction. Acyl- carnitine is formed by extracting a proton from carnitine, whereas acyl-CoA is formed by extracting a proton from CoA. | ||