...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biochemical Pharmacology >Aminotransferase, l-amino acid oxidase and beta-lyase reactions involving l-cysteine S-conjugates found in allium extracts Relevance to biological activity?
【24h】

Aminotransferase, l-amino acid oxidase and beta-lyase reactions involving l-cysteine S-conjugates found in allium extracts Relevance to biological activity?

机译：在葱属提取物中发现的涉及l-半胱氨酸S-缀合物的氨基转移酶，l-氨基酸氧化酶和β-裂合酶反应与生物活性有关吗？

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Several cysteine S-conjugates that occur in extracts of garlic and other plants of the allium family possess anti-oxidant properties, and many, including S-allyl-l-cysteine (SAC) and S-allylmercapto-l-cysteine (SAMC), are promising anti-cancer agents. To understand possible biochemical mechanisms contributing to the protective effects, the ability of selected allium-derived l-cysteine S-conjugates to undergo various enzyme-catalyzed transformations was investigated. SAC, SAMC, S-propylmercapto-l-cysteine and S-penta-1,3-dienylmercapto-l-cysteine were shown to be substrates of: (a) highly purified rat kidney glutamine transaminase K (GTK); (b) purified snake venom l-amino acid oxidase; and (c) a cysteine S-conjugate beta-lyase present in rat liver cytosol. S-Methylmercapto-l-cysteine was shown to be a substrate of GTK and l-amino acid oxidase, but not of the cysteine S-conjugate beta-lyase. Evidence is presented that a major enzyme responsible for the cysteine S-conjugate beta-lyase reactions in the ratliver cytosol is gamma-cystathionase. The possible role of gamma-cystathionase in generating sulfane sulfur from the disulfide-containing cysteine S-conjugates present in allium extracts, and the possible role of this sulfane sulfur in enzyme regulation, targeting of cancer cells and detoxification reactions is discussed. An interesting side finding of the present work is that rat liver mitochondria are more active than rat liver cytosol in catalyzing a cysteine S-conjugate beta-lyase reaction with the mitochondrial protoxicant S-(1,1,2,2-tetrafluoroethyl)-l-cysteine (TFEC) at physiological pH and at low substrate concentration.
机译：大蒜和葱属其他植物的提取物中存在的几种半胱氨酸S-共轭物具有抗氧化特性，其中许多包括S-烯丙基-1-半胱氨酸（SAC）和S-烯丙基巯基-1-半胱氨酸（SAMC），是有前途的抗癌药。为了了解可能的生物化学机制，有助于保护作用，调查了选定的洋葱来源的l-半胱氨酸S-共轭物经历各种酶催化转化的能力。 SAC，SAMC，S-丙基巯基-1-半胱氨酸和S-penta-1,3-二烯基巯基-1-半胱氨酸被证明是：（a）高纯度大鼠肾脏谷氨酰胺转氨酶K（GTK）; （b）纯化的蛇毒l-氨基酸氧化酶; （c）存在于大鼠肝细胞溶胶中的半胱氨酸S-缀合β-裂合酶。已显示S-甲基巯基-1-半胱氨酸是GTK和1-氨基酸氧化酶的底物，而不是半胱氨酸S-缀合物β-裂合酶的底物。证据表明，导致大鼠肝细胞溶胶中半胱氨酸S-共轭β-裂合酶反应的主要酶是γ-胱硫醚酶。讨论了γ-胱硫醚酶可能从葱属提取物中存在的含二硫化物的半胱氨酸S-缀合物中产生硫磺硫的可能作用，以及该硫磺硫在酶调节，靶向癌细胞和排毒反应中的可能作用。本研究有趣的发现是，大鼠肝线粒体在催化半胱氨酸S-共轭β-裂合酶与线粒体前毒素S-（1,1,2,2-四氟乙基）-1的反应中比大鼠肝细胞质更活跃。 -半胱氨酸（TFEC）在生理pH值和低底物浓度下。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号