BIOSYNTHESIS OF URIDINE DIPHOSPHATE D-XYLOSE .3. URIDINE DIPHOSPHATE D-GLUCOSE DEHYDROGENASE OF CRYPTOCOCCUS LAURENTII
BIOSYNTHESIS OF URIDINE DIPHOSPHATE D-XYLOSE .3. URIDINE DIPHOSPHATE D-GLUCOSE DEHYDROGENASE OF CRYPTOCOCCUS LAURENTII
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DOI：
10.1021/bi00870a012
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发表时间：
1966-01-01
期刊：
影响因子：
2.9
通讯作者：
FEINGOLD, DS
中科院分区：
文献类型：
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作者：
ANKEL, H;ANKEL, E;FEINGOLD, DS
尿苷二磷酸D-葡萄糖脱氢酶（EC 1. 1. 1. 22)从罗伦隐球酵母（Cryptococcuslaurentii）中分离纯化了一种新的天然多糖，并对其性质进行了研究。尿苷二磷酸D-葡萄糖是底物;腺苷、胞苷、鸟苷和胸苷的二磷酸葡萄糖衍生物不是底物。烟酰胺腺嘌呤二核苷酸（NAD）、3-乙酰吡啶-AD或硫代烟酰胺-AD作为氢受体具有活性; [α]-NAD、脱氨基-NAD、3-甲酰基吡啶-AD、3-丙酰基吡啶-AD和烟酸乙酯-AD无活性。最佳pH值在7范围内。3-7. 8; Km为0。对于尿苷二磷酸D-葡萄糖和NAD，6 m[图像]。该酶被尿苷二磷酸D-木糖强烈且特异性地抑制;该抑制可以通过增加尿苷二磷酸D-葡萄糖或NAD的浓度来逆转。这些观察结果以及动力学研究表明，抑制是变构的。
Uridine diphosphate D-glucose dehydrogenase (EC 1. 1. 1. 22) from Cryptococcus laurentii has been partially purified and its properties have been investigated. Uridine diphosphate D-glucose is a substrate; the diphosphoglucose derivatives of adenosine, cytidine, guanosine, and thymidine are not substrates. Nicotinamide-adenine dinucleotide (NAD), 3-acetylpyridine-AD, or thionicotinamide-AD are active as hydrogen acceptors; [alpha]-NAD, deamino-NAD, 3-formylpyridine-AD, 3-propionylpyridine-AD, and ethylnicotinate-AD are inactive. The pH optimum is in the range 7. 3-7. 8; Km is 0. 6 m[image] for both uridine diphosphate D-glucose and NAD. The enzyme is strongly and specifically inhibited by uridine diphosphate D-xylose; the inhibition can be reversed by increased concentrations of either uridine diphosphate D-glucose or NAD. These observations as well as kinetic studies show that the inhibition is allosteric.