Hill E J, Chou T H, Shih M C, Park J H
J Biol Chem. 1975 Mar 10;250(5):1734-40.
Glyceraldehyde 3-phosphate dehydrogenase (D-glyceraldehyde-3-phoshate:nicotinamide adenine dinucleotide oxidoreductase (phosphorylating), EC 1.2.1.12) forms a complex with 3-pyridinealdehyde-NAD which survives precipitation with 7% perchloric acid. The molar ratio bound 3-pyridinealdehyde-NAD to the enzyme is 2.5 to 2.9. Lactate, malate, and alcohol dehydrogenases do not form acid-precipitable complexes with 3-pyridinealdehyde-NAD. 3-Pyridinealdehyde-deamino-NAD or glyceraldehyde 3-phosphate also forms an acid-stable complex with glyceraldehyde 3-phosphate dehydrogenase; however, NAD, 3-acetylpyridine-NAD, or thionicotinamide-NAD does not produce an acid-stable complex. Incubation of the glyceraldehyde 3-phosphate dehydrogenase with glyceraldehyde 3-phosphate, acetyl phosphate, iodoacetic acid, or iodosobenzoate inhibits the formation of the acid-stable complex with 3-pyridinealdehyde-NAD. Glyceraldehyde 3-phosphate or 3-pyridinealdehyde-NAD also prevents carboxymethylation of the active site cysteine-149 by[14-C]iodoacetic acid. These studies indicate that the aldehyde group of 3-pyridinealdehyde-NAD forms a thiohemiacetal linkage with cysteine-149 which is the substrate binding site for the dehydrogenase reaction. These findings may account for the fact that 3-pyridinealdehyde-NAD strongly inhibits the dehydrogenase and esterase activities of 3-pyridinealdehyde-NAD forms a thiohemiacetal linkage with cysteine-149 which is the substrate binding site for the dehydrogenase reaction. These findings may account for the fact that 3-pyridinealdehyde-NAD strongly inhibits the dehydrogenase and esterase activities of glyceraldehyde 3-phosphate dehydrogenase which require reduced cysteine-149. However, the analogue does not inhibit the acetyl phosphates activity of the enzyme for which the active site sulfhydryl residues must be oxidized.
甘油醛-3-磷酸脱氢酶（D-甘油醛-3-磷酸：烟酰胺腺嘌呤二核苷酸氧化还原酶（磷酸化），EC 1.2.1.12）与3-吡啶醛-NAD形成一种复合物，该复合物能在7%高氯酸沉淀中存活下来。结合的3-吡啶醛-NAD与酶的摩尔比为2.5至2.9。乳酸脱氢酶、苹果酸脱氢酶和乙醇脱氢酶不会与3-吡啶醛-NAD形成酸可沉淀复合物。3-吡啶醛-脱氨基-NAD或甘油醛-3-磷酸也会与甘油醛-3-磷酸脱氢酶形成酸稳定复合物；然而，NAD、3-乙酰吡啶-NAD或硫代烟酰胺-NAD不会产生酸稳定复合物。用甘油醛-3-磷酸、乙酰磷酸、碘乙酸或碘代苯甲酸孵育甘油醛-3-磷酸脱氢酶会抑制与3-吡啶醛-NAD形成酸稳定复合物。甘油醛-3-磷酸或3-吡啶醛-NAD也能阻止[14-C]碘乙酸对活性位点半胱氨酸-149的羧甲基化。这些研究表明，3-吡啶醛-NAD的醛基与半胱氨酸-149形成硫代半缩醛键，而半胱氨酸-149是脱氢酶反应的底物结合位点。这些发现可能解释了3-吡啶醛-NAD强烈抑制甘油醛-3-磷酸脱氢酶的脱氢酶和酯酶活性这一事实，该反应需要还原型半胱氨酸-149。然而，该类似物不会抑制该酶的乙酰磷酸活性，而该酶的活性位点巯基残基必须被氧化。
