Lewis D, Whateley T L
Department of Pharmacy, University of Strathclyde, Glasgow, UK.
Biomaterials. 1988 Jan;9(1):71-5. doi: 10.1016/0142-9612(88)90073-7.
The enzyme, trypsin, has been used to study conformational changes which occur when protein adsorption onto well-characterized, emulsifier-free, polystyrene latex surface takes place. The adsorption isotherm is of the high affinity, Langmuirian type with plateau adsorption of trypsin of 2.8 mg m-2. The enzymic activity of adsorbed trypsin to low molecular weight substrate is found to decrease as the surface coverage decreases indicating that 'spreading' or unfolding of the native protein conformation, with consequent loss of enzymic activity, occurs. On the close packed surface such 'spreading' is inhibited by steric factors. The view that protein adsorption onto hydrophobic surfaces is dominated by the entropy gain due to protein unfolding to maximize hydrophobic interactions is thus supported.
胰蛋白酶已被用于研究蛋白质吸附到特性明确、无乳化剂的聚苯乙烯乳胶表面时发生的构象变化。吸附等温线属于高亲和力的朗缪尔型，胰蛋白酶的平台吸附量为2.8 mg m-2。发现吸附的胰蛋白酶对低分子量底物的酶活性随着表面覆盖率的降低而降低，这表明天然蛋白质构象发生了“伸展”或展开，从而导致酶活性丧失。在紧密堆积的表面上，这种“伸展”受到空间因素的抑制。因此，支持了蛋白质吸附到疏水表面主要是由于蛋白质展开以最大化疏水相互作用而导致熵增加的观点。
