Irreversible Inactivation of Trypanothione Reductase by Unsaturated Mannich Bases: A Divinyl Ketone as Key Intermediate
作者:Brittany Lee、Holger Bauer、Johannes Melchers、Thomas Ruppert、Lauren Rattray、Vanessa Yardley、Elisabeth Davioud-Charvet、R. Luise Krauth-Siegel
DOI:10.1021/jm0504860
日期:2005.11.1
modified by the Mannich base or the divinyl ketone showed specific alkylation of the active site Cys52 by a 5-(2'chlorophenyl)-3-oxo-4-pentenyl substituent. The reaction mechanism and the site of alkylation differ from those in Plasmodium falciparum thioredoxin reductase where the C-terminal redox active dithiol is modified. After deamination, unsaturated Mannich bases are highly reactive in polycondensation
锥虫硫磷还原酶是一种黄锥虫寄生虫特有的黄素酶。在这里,我们显示不饱和曼尼希碱基不可逆地灭活了锥虫锥虫(恰加斯氏病的病原体)锥虫硫醇还原酶。储存DMSO储备液后,化合物的抑制力会大大提高。潜在中间体的HPLC,NMR和质谱数据表明,二乙烯基酮是使酶失活的活性化合物。曼尼希碱或二乙烯基酮修饰的锥虫硫醚还原酶的ESI-和MALDI-TOF质谱表明,活性位点Cys52通过5-(2'氯苯基)-3-氧代-4-戊烯基取代基进行了特定烷基化。反应机理和烷基化位点与恶性疟原虫硫氧还蛋白还原酶中的C端氧化还原活性二硫醇被修饰的反应机理和烷基化位点不同。脱氨基后,不饱和曼尼希碱在与锥虫硫醇缩聚反应中具有很高的反应性。这些化合物与锥虫硫醇和锥虫硫醇还原酶的相互作用可能解释了它们对布鲁氏锥虫的有效锥虫杀伤作用。