Sandbox 160
From Proteopedia
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== Structure & Function == | == Structure & Function == | ||
| - | The enzyme contains a NAD+ group which functions as a hydrogen acceptor during the course of the reaction which is bound to a Rossman fold. During the catalysis of glyceraldehyde 3-phosphate to 1,3-biphosphoglycerate a hydride ion is enzymatically transferred from the aldehyde group of glyceraldehyde 3-phosphate to the nicotinamide ring of NAD+ reducing it to NADH. The active site of GAPDH contains a cysteine residue which reacts with the glyceraldehyde 3-phosphate molecule through its -SH group. The substrate is covalently bound during the reaction through its aldehyde group to the -SH group and the reaction produces a thiohemiacetal. | + | The enzyme contains a NAD+ group which functions as a hydrogen acceptor during the course of the reaction which is bound to a Rossman fold. During the catalysis of glyceraldehyde 3-phosphate to 1,3-biphosphoglycerate a hydride ion is enzymatically transferred from the aldehyde group of glyceraldehyde 3-phosphate to the nicotinamide ring of NAD+ reducing it to NADH. The active site of GAPDH contains a cysteine residue which reacts with the glyceraldehyde 3-phosphate molecule through its -SH group. The substrate is covalently bound during the reaction through its aldehyde group to the -SH group and the reaction produces a thiohemiacetal. The <scene name='Sandbox_160/Newscene/1'>active site</scene> of the molecule is illustrated below. |
Revision as of 06:24, 22 March 2010
Introduction
Glyceraldehyde 3-Phosphate dehydrogenase (GAPDH) is an Oxidoreductase enzyme and is involved in many important biochemical reactions. This protein is responsible for catalyzing the conversion of glyceraldeyde 3-Phosphate into 1,3-Biphosphoglycerate in a two step coupled mechanism. This conversion occurs during step 6 or the beginning of the "payoff phase" of glycolysis (the second half of the entire process) in which ATP and NADH is produced. A total of 2 NADH and 4 ATP are produced during this phase for a net gain of 2 NADH and 2 ATP for the entire glycolysis pathway per glucose.
Structure & Function
The enzyme contains a NAD+ group which functions as a hydrogen acceptor during the course of the reaction which is bound to a Rossman fold. During the catalysis of glyceraldehyde 3-phosphate to 1,3-biphosphoglycerate a hydride ion is enzymatically transferred from the aldehyde group of glyceraldehyde 3-phosphate to the nicotinamide ring of NAD+ reducing it to NADH. The active site of GAPDH contains a cysteine residue which reacts with the glyceraldehyde 3-phosphate molecule through its -SH group. The substrate is covalently bound during the reaction through its aldehyde group to the -SH group and the reaction produces a thiohemiacetal. The of the molecule is illustrated below.
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