Jeck R, Scholze M, Tischlich A, Woenckhaus C, Zimmermann J
Klinikum der Johann Wolfgang Goethe-Universität, Bundesrepublik Deutschland.
Z Naturforsch C J Biosci. 1995 Jul-Aug;50(7-8):476-86. doi: 10.1515/znc-1995-7-803.
Reactive coenzyme analogues omega-(3-diazoniumpyridinium)alkyl adenosine diphosphate were prepared by reaction of omega-(3-aminopyridinium)alkyl adenosine diphosphate with nitrous acid. In these compounds the nicotinamide ribose is substituted by hydrocarbon chains of varied lengths (n-ethyl to n-pentyl). The diazonium compounds are very unstable and decompose rapidly at room temperature. They show a better stability to 0 degree C. Lactate and alcohol dehydrogenase do not react with any of the analogues. Glyceraldehyde-3-phosphate dehydrogenase reacts rapidly with the diazoniumpentyl compound. Decreasing the length of the alkyl chain significantly decreases the inactivation velocity. 3 alpha, 20 beta-Hydroxysteroid dehydrogenase reacts at 0 degree C with the ethyl homologue and slowly with the propyl compound. The butyl- and pentyl analogues do not inactivate at 0 degree C. Tests with 14C-labeled 2-(3-diazoniumpyridinium)ethyl adenosine diphosphate show that complete loss of enzyme activity results after incorporation of 2 moles of inactivator into 1 mole of tetrameric enzyme. 4-(3-Acetylpyridinium)butyl 2'-phospho-adenosine diphosphate, a structural analogue of NADP+, was prepared by condensation of adenosine-2,3-cyclophospho-5'-phosphomorpholidate with (3-acetylpyridinium)butyl phosphate, followed by hydrolysis of the cyclic phosphoric acid with 2':3'-cyclonucleotide-3'-phosphodiesterase. Because of the redox potential (-315 mV) and the distance between the pyridinium and phosphate groups, this analogue is a hydrogen acceptor and its reduced form a hydrogen donor in tests with alcohol dehydrogenase from Thermoanaerobium brockii. The reduced form of the coenzyme analogue also is a hydrogen donor with glutathione reductase. With other NADP+-dependent dehydrogenases the compound has been shown to be a competitive inhibitor against the natural coenzyme. The acetyl group reacts with bromine to form the bromoacetyl group. This reactive bromoacetyl analogue is a specific active-site directed irreversible inhibitor of isocitrate dehydrogenase.
通过ω-(3-氨基吡啶鎓)烷基二磷酸腺苷与亚硝酸反应制备了反应性辅酶类似物ω-(3-重氮吡啶鎓)烷基二磷酸腺苷。在这些化合物中，烟酰胺核糖被不同长度的烃链（从正乙基到正戊基）取代。重氮化合物非常不稳定，在室温下迅速分解。它们在0℃时表现出较好的稳定性。乳酸脱氢酶和醇脱氢酶与任何一种类似物都不反应。3-磷酸甘油醛脱氢酶与重氮戊基化合物迅速反应。烷基链长度的减少显著降低了失活速度。3α,20β-羟基类固醇脱氢酶在0℃时与乙基同系物反应，与丙基化合物反应缓慢。丁基和戊基类似物在0℃时不会失活。用14C标记的2-(3-重氮吡啶鎓)乙基二磷酸腺苷进行的试验表明，在将2摩尔失活剂掺入1摩尔四聚体酶后，酶活性完全丧失。4-(3-乙酰吡啶鎓)丁基2'-磷酸-腺苷二磷酸是NADP+的结构类似物，通过腺苷-2,3-环磷酸-5'-磷酰吗啉酸酯与(3-乙酰吡啶鎓)丁基磷酸缩合，然后用2':3'-环核苷酸-3'-磷酸二酯酶水解环磷酸制备。由于氧化还原电位（-315 mV）以及吡啶鎓和磷酸基团之间的距离，这种类似物在使用来自布氏嗜热厌氧菌的醇脱氢酶进行的试验中是氢受体，其还原形式是氢供体。辅酶类似物的还原形式也是谷胱甘肽还原酶的氢供体。对于其他依赖NADP+的脱氢酶，该化合物已被证明是天然辅酶的竞争性抑制剂。乙酰基与溴反应形成溴乙酰基。这种反应性溴乙酰类似物是异柠檬酸脱氢酶的特异性活性位点导向不可逆抑制剂。
