Jasper Small Lactate Sandbox 1: Difference between revisions
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==Function== | ==Function== | ||
[[Image:LDH_reaction.jpeg|left|thumb|355px|Catalytic function of LDH]] | [[Image:LDH_reaction.jpeg|left|thumb|355px|Catalytic function of LDH]] | ||
LDH preforms an important metabolic function in the body. The enzyme catalyzes both the conversion of pyruvate to lactose as well as the conversion of lactose to pyruvate. The conversion of pyruvate to lactose occurs in the muscles of the body when oxygen is absent. The lactate acid is then moved back to the liver where LDH catalyzes the Cori cycle which converts the lactose back into pyruvate. The reaction is also important as it is coupled with the interconversion of NADH and NAD+. | |||
==Catalysis== | ==Catalysis== | ||
Studies have shown that the reaction mechanism of LDH follows an ordered sequence. In order for lactate to be oxidized NAD+ must bind to the enzyme first followed by lactate. Transfer of a hydride ion then happens quickly in either direction giving a mixture of the two teranary complexes, enzyme-NAD+-lactate and enzyme-NADH-pyruvate. Finally pyruvate dissociates from the enzyme followed by NADH. The rate limiting step in this reaction is the rate of dissociation of NADH. The same holds true in the reverse reaction that the coenzyme, NADH, must bind first before the substrate, pyruvate, can bind. The conversion of pyruvate to lactate with the subsequent regeneration of NAD+ is a very favorable(1). | Studies have shown that the reaction mechanism of LDH follows an ordered sequence. In order for lactate to be oxidized NAD+ must bind to the enzyme first followed by lactate. Transfer of a hydride ion then happens quickly in either direction giving a mixture of the two teranary complexes, enzyme-NAD+-lactate and enzyme-NADH-pyruvate. Finally pyruvate dissociates from the enzyme followed by NADH. The rate limiting step in this reaction is the rate of dissociation of NADH. The same holds true in the reverse reaction that the coenzyme, NADH, must bind first before the substrate, pyruvate, can bind. The conversion of pyruvate to lactate with the subsequent regeneration of NAD+ is a very favorable(1). | ||
[[Image:2nd.jpeg|left|thumb|355px|]] | |||
Important Sites: | Important Sites: | ||
*<scene name='Jasper_Small_Lactate_Sandbox_1/His_195/1'>HIS 195</scene> | *<scene name='Jasper_Small_Lactate_Sandbox_1/His_195/1'>HIS 195</scene> | ||