Macias-Sánchez Elena, Meruvia-Rojas Yumeida, Cartwright Julyan H E, Checa Antonio G, Sainz-Díaz C Ignacio
Department of Stratigraphy and Paleontology, University of Granada, Granada 18071, Spain.
Instituto Andaluz de Ciencias de la Tierra (IACT-CSIC), Armilla 18100, Granada, Spain.
J Struct Biol. 2025 Mar;217(1):108165. doi: 10.1016/j.jsb.2024.108165. Epub 2024 Dec 26.
The nacre formation process is a fascinating phenomenon involving mineral phase transformations, self-assembly processes, and protein-mineral interactions, resulting in a hierarchical structure that exhibits outstanding mechanical properties. However, this process is only partially known, and many aspects of nacre structure are not well understood, especially at the molecular scale. To understand the interplay between components-aragonite, protein and chitin-of the structure of nacre observed experimentally, we investigate the interactions of a peptide that is part of the protein lustrin A, identified in the nacreous layer of the shell of the abalone Haliotis rufescens, with the (001) crystal surface of aragonite and the chitin molecule. We report the results of atomistic molecular-modelling calculations and molecular-dynamics simulations of the peptide interacting with both the aragonite surface and the chitin polymer. The peptide shows an energetically favourable binding to the aragonite surface. The interaction of the carboxylic groups of the glutamic unit with the crystalline surface is essential to reproduce the characteristic elastomeric properties of this peptide in nacre.
珍珠层形成过程是一个迷人的现象，涉及矿物相转变、自组装过程以及蛋白质-矿物相互作用，最终形成具有卓越机械性能的层级结构。然而，这一过程仅被部分了解，珍珠层结构的许多方面尚未得到充分认识，尤其是在分子尺度上。为了理解通过实验观察到的珍珠层结构中各组分——文石、蛋白质和几丁质——之间的相互作用，我们研究了一种肽与文石的(001)晶体表面以及几丁质分子之间的相互作用，该肽是在红鲍（Haliotis rufescens）贝壳珍珠层中鉴定出的蛋白质光泽蛋白A的一部分。我们报告了该肽与文石表面和几丁质聚合物相互作用的原子分子模型计算和分子动力学模拟结果。该肽显示出与文石表面具有能量上有利的结合。谷氨酸单元的羧基与晶体表面的相互作用对于重现该肽在珍珠层中特有的弹性性能至关重要。
