...
首页> 外文期刊>Canadian Journal of Physiology and Pharmacology >Conversion of renin substrate tetradecapeptide to angiotensin II by rat MAB elastase-2.
【24h】

Conversion of renin substrate tetradecapeptide to angiotensin II by rat MAB elastase-2.

机译:大鼠MAB弹性蛋白酶2将肾素底物四肽转化为血管紧张素II。

获取原文
获取原文并翻译 | 示例
           

摘要

A new approach for the purification of rat mesenteric arterial bed (MAB) elastase-2 has been developed using the chromogenic substrates N-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide and N-succinyl-Ala-Ala-Pro-Leu-p-nitroanilide to monitor the enzymatic activity during various stages of purification. The purified enzyme was evaluated in the presence of various inhibitors and confirmed to have angiotensin (Ang) II-forming ability. The active site-directed inhibitor acetyl-Ala-Ala-Pro-Leu-chloromethylketone (100 micromol x L(-1)), described for human pancreatic elastase-2, abolished the enzymatic activity, confirming that the enzyme is an elastase-2. Chymostatin (100 micromol x L(-1)), an inhibitor regarded as selective for chymases, also showed a remarkable inhibitory effect (94%), whereas captopril (100 micromol x L(-1)) had no effect at all on the Ang II-forming activity. The Ang II precursor renin substrate tetradecapeptide (RS-14P) was converted into Ang II by the rat MAB elastase-2 with the following kinetic constants: Km = 124 +/- 21 micromol x L(-1); Kcat = 629 min(-1); catalytic efficiency (Kcat /Km) = 5.1 min(-1) micro(mol/L)-1. In conclusion, the strategy for the purification of rat MAB elastase-2 with the chromogenic substrates proved to be simple, rapid, accurate, and highly reproducible; therefore, it can be reliably and conveniently used to routinely purify this enzyme. The kinetic parameters for the formation of Ang II from RS-14P by rat MAB elastase-2 emphasize differences in substrate specificity between this and other Ang II-forming enzymes.
机译:已开发了使用生色底物N-琥珀酰-丙氨酸-丙氨酸-脯氨酸-苯丙氨酸-对硝基苯胺和N-琥珀酰-丙氨酸-丙氨酸-脯氨酸-纯化大鼠肠系膜动脉床(MAB)弹性蛋白酶2的新方法。对-硝基硝基苯胺可监控纯化的各个阶段的酶活性。在各种抑制剂的存在下评估纯化的酶,并确认其具有血管紧张素(Ang)II形成能力。活性定点抑制剂乙酰-丙氨酸-丙氨酸-脯氨酸-Leu-氯甲基酮(100 micromol x L(-1)),针对人类胰腺弹性蛋白酶-2的描述取消了酶活性,证实该酶为弹性蛋白酶-2。 。胰凝乳蛋白酶抑制剂(100 micromol x L(-1))被视为对乳糜菌具有选择性,也显示出显着的抑制作用(94%),而卡托普利(100 micromol x L(-1))完全没有抑制作用。 Ang II形成活动。大鼠MAB弹性蛋白酶2将Ang II前体肾素底物四肽(RS-14P)转化为Ang II,其动力学常数为:Km = 124 +/- 21 micromol x L(-1); Kcat = 629分钟(-1);催化效率(Kcat / Km)= 5.1 min(-1)micro(mol / L)-1。总之,用生色底物纯化大鼠MAB弹性蛋白酶2的策略被证明是简单,快速,准确且可重现的。因此,可以可靠,方便地常规纯化该酶。大鼠MAB弹性蛋白酶2从RS-14P形成Ang II的动力学参数强调了该酶与其他形成Ang II的酶之间底物特异性的差异。

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