Lactate Dehydrogenase: Difference between revisions
Michal Harel (talk | contribs) No edit summary |
No edit summary |
||
| Line 19: | Line 19: | ||
===Catalysis=== | ===Catalysis=== | ||
Studies have shown that the reaction mechanism of LDH follows an ordered sequence. [[Image:LDH_reaction.jpeg|355px|Catalytic function of LDH (1)]] | Studies have shown that the reaction mechanism of LDH follows an ordered sequence. | ||
[[Image:LDH_reaction.jpeg|355px|Catalytic function of LDH (1)]] | |||
{{Clear}} | {{Clear}} | ||
In order for lactate to be oxidized NADH must bind to the enzyme first followed by lactate. <scene name='Lactate_Dehydrogenase/Secondary/5'>Several residues are involved in the binding of NADH</scene>. Once the NADH is bound to the enzyme, it is then possible for lactate to bind (substrate oxamate is shown; the ‑CH3 group is replaced by ‑NH2 to form oxamate). Lactate binds to the enzyme between the nicotinamide ring and several LDH residues. Transfer of a hydride ion then happens quickly in either direction giving a mixture of the two tertiary complexes, enzyme-NAD+-lactate and enzyme-NADH-pyruvate .Finally pyruvate dissociates from the enzyme followed by NAD+<ref name="1st"> http://www.bioc.aecom.yu.edu/labs/calllab/highlights/LDH.htm</ref>. | In order for lactate to be oxidized NADH must bind to the enzyme first followed by lactate. <scene name='Lactate_Dehydrogenase/Secondary/5'>Several residues are involved in the binding of NADH</scene>. Once the NADH is bound to the enzyme, it is then possible for lactate to bind (substrate oxamate is shown; the ‑CH3 group is replaced by ‑NH2 to form oxamate). Lactate binds to the enzyme between the nicotinamide ring and several LDH residues. Transfer of a hydride ion then happens quickly in either direction giving a mixture of the two tertiary complexes, enzyme-NAD+-lactate and enzyme-NADH-pyruvate .Finally pyruvate dissociates from the enzyme followed by NAD+<ref name="1st"> http://www.bioc.aecom.yu.edu/labs/calllab/highlights/LDH.htm</ref>. | ||