Gross M, Auerbach G, Jaenicke R
Institut für Biophysik und physikalische Biochemie, Universität Regensburg, Germany.
FEBS Lett. 1993 Apr 26;321(2-3):256-60. doi: 10.1016/0014-5793(93)80120-j.
High hydrostatic pressures in the biologically relevant range (< or = 1,200 bar) are known to cause dissociation of oligomeric enzymes in vitro, whereas protein denaturation requires pressures far beyond this range. Pressure-induced inactivation phenomena attributable to neither of these effects are shown to occur in monomeric enzymes. Three different types of pressure dependence can be distinguished: (1) a linear dependence of catalytic rate constants on pressure, as predicted by the activated complex theory, observed for lysozyme and thermolysin; (2) a biphasic profile consisting of two linear contributions, found for trypsin; (3) maximum curves, as observed for both directions of the octopine dehydrogenase reaction. The third case may be ascribed to a pressure-induced decrease in the partial specific volume of the protein, resulting in reduced flexibility of the active site. This mechanism may also apply to the pressure-induced inactivation of assembly systems stabilized against dissociation in the cell.
已知在生物学相关范围内（≤1200巴）的高静水压会导致体外寡聚酶解离，而蛋白质变性则需要远高于此范围的压力。在单体酶中未发现可归因于这两种效应的压力诱导失活现象。可以区分三种不同类型的压力依赖性：（1）催化速率常数对压力的线性依赖性，如活化络合物理论所预测，在溶菌酶和嗜热菌蛋白酶中观察到；（2）由两个线性部分组成的双相曲线，在胰蛋白酶中发现；（3）八氢番茄红素脱氢酶反应两个方向均观察到的最大值曲线。第三种情况可能归因于压力诱导蛋白质的比容减小，导致活性位点的灵活性降低。这种机制也可能适用于细胞中稳定防止解离的组装系统的压力诱导失活。
