Inhibition of papain-like cysteine proteases and legumain by caspase-specific inhibitors:: when reaction mechanism is more important than specificity
Inhibition of papain-like cysteine proteases and legumain by caspase-specific inhibitors:: when reaction mechanism is more important than specificity
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DOI：
10.1038/sj.cdd.4401247
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发表时间：
2003-08-01
影响因子：
12.4
通讯作者：
Turk, B
中科院分区：
文献类型：
--
作者：
Rozman-Pungercar, J;Kopitar-Jerala, N;Turk, B
我们在此报告，许多常用的小肽半胱天冬酶抑制剂由与氯甲基酮、氟甲基酮或醛反应基团连接的半胱天冬酶识别序列组成，可有效抑制半胱天冬酶以外的其他半胱氨酸蛋白酶。体外研究包括组织蛋白酶 B、H、L、S、K、F、V、X 和 C、木瓜蛋白酶和 Legumain。 Z-DEVD-cmk 在体外被证明是大多数组织蛋白酶的首选不可逆抑制剂，其次是 Z-DEVD-fmk、Ac-YVAD-cmk、Z-YVAD-fmk 和 Z-VAD-fmk。所有研究的抑制剂对legumain 的灭活作用是中等的，而组织蛋白酶H 和C 的抑制效果很差或根本不被抑制。醛类的抑制作用不是很有效。所有三种氟甲基酮在浓度为 100 μM 时都能有效抑制 Jurkat 和人胚胎肾 293 细胞中的组织蛋白酶。此外，它们以低至 1 μM 的浓度完全抑制组织提取物中的组织蛋白酶 B 和 X 活性。这些结果表明，应谨慎对待基于这些抑制剂的使用的数据，并且其他蛋白酶可能与先前仅归因于半胱天冬酶的过程有关。
We report here that a number of commonly used small peptide caspase inhibitors consisting of a caspase recognition sequence linked to chloromethylketone, fluoromethylketone or aldehyde reactive group efficiently inhibit other cysteine proteases than caspases. The in vitro studies included cathepsins B, H, L, S, K, F, V, X and C, papain and legumain. Z-DEVD-cmk was shown to be the preferred irreversible inhibitor of most of the cathepsins in vitro, followed by Z-DEVD-fmk, Ac-YVAD-cmk, Z-YVAD-fmk and Z-VAD-fmk. Inactivation of legumain by all the inhibitors investigated was moderate, whereas cathepsins H and C were poorly inhibited or not inhibited at all. Inhibition by aldehydes was not very potent. All the three fluoromethylketones efficiently inhibited cathepsins in Jurkat and human embryonic kidney 293 cells at concentrations of 100 muM. Furthermore, they completely inhibited cathepsins B and X activity in tissue extracts at concentrations as low as 1 muM. These results suggest that data based on the use of these inhibitors should be taken with caution and that other proteases may be implicated in the processes previously ascribed solely to caspases.