Anderson A B, Robertson C R
Department of Chemical Engineering, Stanford University, California 94305, USA.
Biophys J. 1995 May;68(5):2091-7. doi: 10.1016/S0006-3495(95)80388-7.
To assess the effects of adsorption on protein structure, ultraviolet optical absorption spectra of myoglobin (Mb) bound to polydimethylsiloxane (PDMS) were measured. A flow cell, which enabled adsorption under controlled hydrodynamic conditions, was used in conjunction with a conventional spectrophotometer to obtain the spectra. Adsorption to PDMS reduced significantly the absorbance in the Soret region of the Mb spectrum, whereas the spectrum in the region near 280 nm was essentially unaffected. This result showed that disruption of the native structure of Mb occurs following interaction with PDMS. Furthermore, the change in the absorption spectrum may indicate loss of heme from the heme pocket of the adsorbed protein. Mb structure was altered from its solution configuration within fifteen min of contact with the surface. Exchange of adsorbed Mb with Mb in solution had little or no effect on the absorption spectrum of the surface-confined protein, indicating that exchange occurs only between conformationally altered species or between native species.
为评估吸附对蛋白质结构的影响，测量了与聚二甲基硅氧烷（PDMS）结合的肌红蛋白（Mb）的紫外光吸收光谱。使用一个能够在可控流体动力学条件下进行吸附的流通池，并结合传统分光光度计来获取光谱。吸附到PDMS上显著降低了Mb光谱索雷特区域的吸光度，而在280nm附近区域的光谱基本未受影响。这一结果表明，Mb与PDMS相互作用后其天然结构发生了破坏。此外，吸收光谱的变化可能表明吸附蛋白的血红素口袋中血红素的丢失。Mb结构在与表面接触的15分钟内就从其溶液构型发生了改变。吸附的Mb与溶液中的Mb交换对表面受限蛋白的吸收光谱几乎没有影响，这表明交换仅发生在构象改变的物种之间或天然物种之间。
