†MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Chemical and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington 6140, New Zealand.
‡Riddet Institute, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand.
Biomacromolecules. 2015 Jun 8;16(6):1855-61. doi: 10.1021/acs.biomac.5b00467. Epub 2015 May 26.
Protein adsorption at liquid-liquid interfaces is of immense relevance to many biological processes and dairy-based functional foods. Due to experimental limitations, however, there is still a remarkable lack of understanding of the adsorption mechanism, particularly at a molecular level. In this study, atomistic molecular dynamics simulations were used to elucidate the approach and adsorption mechanism of β-lactoglobulin (β-LG) at a decane-water interface. Through multiple independent simulations starting from three representative initial orientations of β-LG relative to the decane surface the rate at which β-LG approaches the oil/water interface is found to be independent of its initial orientation, and largely stochastic in nature. While the residues that first make contact with the decane and the final orientation of β-LG upon adsorption are similar in all cases, the adsorption process is driven predominantly by structural rearrangements that preserve the secondary structure but expose hydrophobic residues to the decane surface. This detailed characterization of the adsorption of β-LG at an oil/water interface should inform the design and development of novel encapsulation and delivery systems in the food and pharmaceutical sciences.
蛋白质在液-液界面的吸附对于许多生物过程和基于乳制品的功能性食品都具有重要意义。然而，由于实验限制，人们对吸附机制，特别是在分子水平上的吸附机制，仍然缺乏了解。在这项研究中，使用原子分子动力学模拟阐明了β-乳球蛋白（β-LG）在癸烷-水界面的接近和吸附机制。通过从β-LG 相对于癸烷表面的三个代表性初始取向开始的多个独立模拟，发现β-LG 接近油水界面的速率与其初始取向无关，并且在很大程度上是随机的。虽然所有情况下与癸烷最先接触的残基和吸附后β-LG 的最终取向相似，但吸附过程主要由结构重排驱动，这些结构重排保持了二级结构，但使疏水性残基暴露于癸烷表面。这种对β-LG 在油/水界面上吸附的详细特征描述应该为食品和制药科学中新型封装和输送系统的设计和开发提供信息。
