Artusio Fiora, Gavira José A, Pisano Roberto
Department of Applied Science and Technology, Politecnico di Torino, 24 Corso Duca degli Abruzzi, 10129 Torino, Italy.
Laboratorio de Estudios Cristalográficos, Instituto Andaluz de Ciencias de la Tierra (Consejo Superior de Investigaciones Científicas-Universidad de Granada), Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain.
Cryst Growth Des. 2023 Mar 31;23(5):3195-3201. doi: 10.1021/acs.cgd.2c01377. eCollection 2023 May 3.
Modified surfaces like siliconized glass are commonly used to support protein crystallization and facilitate obtaining crystals. Over the years, various surfaces have been proposed to decrease the energetic penalty required for consistent protein clustering, but scarce attention has been paid to the underlying mechanisms of interactions. Here, we propose self-assembled monolayers that are surfaces exposing fine-tuned moieties with a very regular topography and subnanometer roughness, as a tool to unveil the interaction between proteins and functionalized surfaces. We studied the crystallization of three model proteins having progressively narrower metastable zones, i.e., lysozyme, catalase, and proteinase K, on monolayers exposing thiol, methacrylate, and glycidyloxy groups. Thanks to comparable surface wettability, the induction or the inhibition of nucleation was readily attributed to the surface chemistry. For example, thiol groups strongly induced the nucleation of lysozyme thanks to electrostatic pairing, whereas methacrylate and glycidyloxy groups had an effect comparable to unfunctionalized glass. Overall, the action of surfaces led to differences in nucleation kinetics, crystal habit, and even crystal form. This approach can support the fundamental understanding of the interaction between protein macromolecules and specific chemical groups, which is crucial for many technological applications in the pharmaceutical and food industry.
诸如硅化玻璃之类的改性表面通常用于支持蛋白质结晶并有助于获得晶体。多年来，人们提出了各种表面来减少一致的蛋白质聚集所需的能量消耗，但对相互作用的潜在机制却很少关注。在这里，我们提出自组装单分子层，即具有非常规则的形貌和亚纳米粗糙度的暴露精细调节部分的表面，作为揭示蛋白质与功能化表面之间相互作用的工具。我们研究了在暴露硫醇、甲基丙烯酸酯和缩水甘油氧基的单分子层上，三种具有逐渐变窄的亚稳区的模型蛋白质（即溶菌酶、过氧化氢酶和蛋白酶K）的结晶情况。由于具有可比的表面润湿性，成核的诱导或抑制很容易归因于表面化学。例如，硫醇基团由于静电配对强烈诱导溶菌酶的成核，而甲基丙烯酸酯和缩水甘油氧基的作用与未功能化的玻璃相当。总体而言，表面的作用导致成核动力学、晶体习性甚至晶体形态的差异。这种方法有助于从根本上理解蛋白质大分子与特定化学基团之间的相互作用，这对于制药和食品工业中的许多技术应用至关重要。
