Aldoximes: active-site probes of alcohol dehydrogenases.
Aldoximes: active-site probes of alcohol dehydrogenases.
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醛肟：乙醇脱氢酶的活性位点探针。
DOI：
10.1111/j.1432-1033.1982.tb06812.x
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发表时间：
1982
期刊：
影响因子：
--
通讯作者：
Anderson,RE
中科院分区：
文献类型：
--
作者：
Sigman,DS;Frolich,M;Anderson,RE
脂肪醛的肟类抑制马肝和酵母醇脱氢酶。肟类对这些酶的抑制模式反映了它们的底物特异性。例如，乙醛肟比丁醛肟(K10.06 mM和2 mM)是更有效的酵母酶抑制剂。对肝酶来说，丁醛肟的K1为6.6nM，乙醛肟的K1为0.68nM。己醛、八醛和十醛对肝酶的抑制常数分别为2 nM、1 nM和0.7 nM。脂肪肟对肝酶的抑制是由于对映体与酶和NAD+形成光谱可识别的三元络合物。所有配合物都有一个跃迁，其最大吸收波长为2 90-30 5 nm，吸收系数约为7 mM−1 cm−1，这很可能是由于在辅酶的烟酰胺部分上加成了肟羟基所致。与酵母醇脱氢酶不形成类似的复合体。由于由稳态抑制数据确定的解离常数以及光谱可识别的络合物的形成和解离动力学是相同的，因此酶-NAD+-肟络合物一定是观察到的抑制的唯一原因，即使与NADH也形成了三元络合物。与对二甲氨基肉桂醛生成的三元络合物在290-305 nm处有特征吸收，表明烟酰胺部分加成了氧，此外，在330 nm到425 nm的长波跃迁中，锌离子发生了光谱漂移，表明锌离子被肟氮配位。抗氧化剂在结构上与4-烷基吡唑同源，后者也是非常有效的马肝醇脱氢酶抑制剂。酵母酶对吡唑和肟类化合物的相对不敏感性表明，锌离子在这两种酶中的催化作用不能完全相同。
The oximes of aliphatic aldehydes inhibit horse liver and yeast alcohol dehydrogenase. The pattern of inhibition of these enzymes by the oximes reflects their substrate specificity. For example, acetaldoxime is a more effective inhibitor of the yeast enzyme than butyraldoxime (K10.06 mM and 2 mM respectively). However, for the liver enzyme, theK1for butyraldoxime is 6.6 nM while that for acetaldoxime is 0.68 μM. The inhibition constants of hexaldoxime, octaldoxime and decaldoxime for the liver enzyme are 2 nM, 1 nM and 0.7 nM, respectively.The inhibition of the liver enzyme by the aliphatic oxime is attributable to theantiisomer which forms spectroscopically identifiable ternary complexes with the enzyme and NAD+. All complexes exhibit a transition with a maximal absorption from 290–305 nm and an absorption coefficient of approximately 7 mM−1cm−1which most likely results from the addition of the hydroxyl group of the oxime to the nicotinamide moiety of the coenzyme. An analogous complex is not formed with yeast alcohol dehydrogenase. Since the dissociation constants determined from steady‐state inhibition data and the kinetics of formation and dissociation of the spectroscopically identifiable complex are identical, the enzyme‐NAD+‐oxime complex must be exclusively responsible for the observed inhibition, even though ternary complexes with NADH also form. The ternary complex formed with the oxime ofp‐dimethylaminocinnamaldehyde has the characteristic absorption at 290–305 nm, indicative of oxygen addition to the nicotinamide moiety, and in addition exhibits a spectral shift in its long‐wavelength transition from 330 nm to 425 nm, suggestive of inner‐sphere coordination of the zinc ion by the nitrogen of the oxime.Anti‐oximes are structurally homologous to 4‐alkyl pyrazoles which are also very effective inhibitors of horse liver alcohol dehydrogenase. The relative insensitivity of the yeast enzyme to pyrazole and oximes suggests that the catalytic function of the zinc ion in these two enzymes cannot be assumed to be identical.
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大鼠肝脏乙醇脱氢酶催化的吡唑抑制和乙醇和视黄醇氧化的动力学研究。
DOI：
10.3891/acta.chem.scand.23-1119
发表时间：
1969
期刊：
Acta chemica Scandinavica
影响因子：
--
作者：
M. Reynier
通讯作者：
M. Reynier
DOI：
10.1016/s0021-9258(18)62677-8
发表时间：
1970
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
R. Colman;D. Foster
通讯作者：
D. Foster
脂肪酸酰胺与马肝乙醇脱氢酶和NA的三元复合物。
DOI：
10.1016/0005-2744(70)90097-5
发表时间：
1970
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
D. Sigman;A. D. Winer
通讯作者：
A. D. Winer
羟胺与二磷吡啶核苷酸的化学反应。
DOI：
10.1016/s0021-9258(18)71234-9
发表时间：
1954
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
R. Burton;N. Kaplan
通讯作者：
N. Kaplan
影响因子：
2.9
作者：
KIM, CSY;CHAYKIN, S
通讯作者：
CHAYKIN, S