磷酸葡萄糖酸脫氫酶 (脫羧)

磷酸葡萄糖酸脫氫酶 (脫羧)（英語：phosphogluconate dehydrogenase (decarboxylating)，EC 1.1.1.44 （頁面存檔備份，存於網際網路檔案館））是一種以NAD⁺或NADP⁺為受體、作用於供體CH-OH基團上的氧化還原酶。這種酶能催化以下酶促反應：

6-磷酸-D-葡萄糖酸 + NADP⁺ ${\displaystyle \rightleftharpoons }$ D-核酮糖5-磷酸 + CO₂ + NADPH

磷酸葡萄糖酸脫氫酶 (脫羧)
命名 系統命名 6-phospho-D-gluconate:NADP+ 2-oxidoreductase (decarboxylating) 縮寫 別名 phosphogluconic acid dehydrogenase; 6-phosphogluconic dehydrogenase; 6-phosphogluconic carboxylase; 6-phosphogluconate dehydrogenase (decarboxylating); 6-phospho-D-gluconate dehydrogenase
識別碼
EC編號	1.1.1.44
CAS號	9073-95-4
資料庫
IntEnz	IntEnz瀏覽
BRENDA（英語：BRENDA）	BRENDA入口
ExPASy（英語：ExPASy）	NiceZyme瀏覽
KEGG	KEGG入口
MetaCyc（英語：MetaCyc）	代謝路徑
PRIAM（英語：PRIAM_enzyme-specific_profiles）	概述
PDB	RCSB PDB PDBj PDBe PDBsum
基因本體	AmiGO / EGO
搜索 PMC 相關文獻 PubMed 相關文獻

在上述反應中，6-磷酸葡萄糖酸首先被氧化為3-酮-6-磷酸葡萄糖酸，同時NADPH形成並被釋放；然後，中間體被脫羧產生1,2-烯二醇式結構，最終互變異構化為核酮糖5-磷酸。^[1] 高濃度的NADPH對這種酶的活性有抑制性，而6-磷酸葡萄糖酸則能激活這種酶。^[2] 磷酸葡萄糖酸脫氫酶 (脫羧)主要參與核酮糖5-磷酸的產生，並為磷酸戊糖途徑提供主要的NADPH。^[3]

參考文獻

1. Chen YY, Ko TP, Chen WH, Lo LP, Lin CH, Wang AH. Conformational changes associated with cofactor/substrate binding of 6-phosphogluconate dehydrogenase from Escherichia coli and Klebsiella pneumoniae: Implications for enzyme mechanism. J Struct Biol. 2010, 169 (1): 25–35. PMID 19686854. doi:10.1016/j.jsb.2009.08.006.
2. Rippa M, Giovannini PP, Barrett MP, Dallocchio F, Hanau S. 6-Phosphogluconate dehydrogenase: the mechanism of action investigated by a comparison of the enzyme from different species. Biochim Biophys Acta. 1998, 1429 (1): 83–92. PMID 9920387. doi:10.1016/S0167-4838(98)00222-2.
3. He, W., Wang, Y., Liu, W. & Zhou, C.-Z. Crystal structure of Saccharomyces cerevisiae 6-phosphogluconate dehydrogenase Gnd1. BMC Struct. Biol. 2007,. 7, (38): 38. PMC 1919378 . PMID 17570834. doi:10.1186/1472-6807-7-38.

• DICKENS F, GLOCK GE. Direct oxidation of glucose-6-phosphate, 6-phosphogluconate and pentose-5-phosphates by enzymes of animal origin. Biochem. J. 1951, 50 (1): 81–95. PMC 1197610 . PMID 14904376.
• Bonsignore A and Horecker BL. Purification and properties of beta-L-hydroxy acid dehydrogenase II. Isolation of beta-keto-L-gluconic acid, an intermediate in L-xylulose biosynthesis. J. Biol. Chem. 1961, 236: 2975–2980.
• Scott DBM and Cohen SS. The oxidative pathway of carbohydrate metabolism in Escherichia coli. 1. The isolation and properties of glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase. Biochem. J. 1953, 55: 23–33.
• Scott DBM and Cohen SS. The oxidative pathway of carbohydrate metabolism in Escherichia coli. 5. Isolation and identification of ribulose phosphate produced from 6-phosphogluconate by the dehydrogenase of E. coli. Biochem. J. 1957, 65: 686–689.