Druzhinina T N, Kusov Y Y, Shibaev V N, Kochetkov N K
Biochim Biophys Acta. 1975 Sep 22;403(1):1-8. doi: 10.1016/0005-2744(75)90002-9.
Analogs of uridine diphosphate glucose (UDPGlc) with a modified hexosyl residue which contained a deoxy-unit at C-3 or C-4 were tested as substrates of calf liver UDPGlc dehydrogenase (EC 1.1.1.22). The 3-deoxyglucose derivative was found not to serve as a substrate for the enzyme whereas the 4-deoxyglucose analog was able to participate in the reaction. The apparent Km of the latter was 5.3 times that of UDPGlc and the relative V was 0.04. The reaction product was identified as uridine diphosphate deoxyhexuronic acid. UDP-deoxyhexoses were non-competitive inhibitors of UDPGlc enzymic oxidation, inhibition increased in the sequence: 2-deoxy-less than 3-and 6-deoxy-less than 4-deoxyglucose derivative. The significance of different HO-groups in hexosyl residue for interaction of UDPGlc with the enzyme is discussed.
对在己糖基残基上有修饰且在C-3或C-4位含有脱氧单元的尿苷二磷酸葡萄糖（UDPGlc）类似物作为小牛肝UDPGlc脱氢酶（EC 1.1.1.22）的底物进行了测试。发现3-脱氧葡萄糖衍生物不能作为该酶的底物，而4-脱氧葡萄糖类似物能够参与反应。后者的表观Km是UDPGlc的5.3倍，相对V为0.04。反应产物被鉴定为尿苷二磷酸脱氧己糖醛酸。UDP-脱氧己糖是UDPGlc酶促氧化的非竞争性抑制剂，抑制作用按以下顺序增加：2-脱氧＜3-和6-脱氧＜4-脱氧葡萄糖衍生物。讨论了己糖基残基中不同羟基对UDPGlc与酶相互作用的重要性。
