百里酚：一种对肌球蛋白具有双重作用（增强和抑制）的经典小分子化合物。

Thymol: a classical small-molecule compound that has a dual effect (potentiating and inhibitory) on myosin.

作者信息

Tamura Takumi, Iwamoto Hiroyuki

机构信息

Structural Biochemistry Laboratory, RIKEN Harima Institute, SPring-8, Hyogo 679-5148, Japan.

出版信息

Biochem Biophys Res Commun. 2004 Jun 4;318(3):786-91. doi: 10.1016/j.bbrc.2004.04.085.

DOI:10.1016/j.bbrc.2004.04.085

PMID:15144906

Abstract

The effect of thymol on the ATPase activity of myosin subfragment-1 (S1) and on the contractile properties of skinned skeletal muscle fibers was studied. At concentrations of 1.5-2 mM, thymol activated the S1 ATPase substantially and the actin-activated S1 ATPase modestly. At the same concentrations, the isometric force of skinned skeletal muscle fibers was modestly suppressed (11% at 2 mM). However, the kinetic parameters of contraction were suppressed more: the velocity of shortening and the rate of force redevelopment after shortening were suppressed by 43% and 31% at 2 mM, respectively. Thus, among other small-molecule inhibitors, thymol is unique in that it has opposite effects on the enzymatic activity and kinetic parameters of contraction. Thymol may serve as a potent tool for studying the mechanism of coupling between the ATPase reaction and contraction in muscle.

摘要

研究了百里酚对肌球蛋白亚片段-1（S1）的ATP酶活性以及对去皮肤骨骼肌纤维收缩特性的影响。在浓度为1.5 - 2 mM时，百里酚显著激活S1 ATP酶，对肌动蛋白激活的S1 ATP酶有适度激活作用。在相同浓度下，去皮肤骨骼肌纤维的等长力受到适度抑制（2 mM时为11%）。然而，收缩的动力学参数受到的抑制更大：在2 mM时，缩短速度和缩短后力的恢复速率分别被抑制了43%和31%。因此，在其他小分子抑制剂中，百里酚的独特之处在于它对酶活性和收缩动力学参数有相反的影响。百里酚可作为研究肌肉中ATP酶反应与收缩之间偶联机制的有力工具。