Laboratoire des Polymères, Institut des Matériaux and Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
Department of Chemistry and Centre for Scientific Computing, University of Warwick, Coventry, UK.
Nat Commun. 2021 May 11;12(1):2675. doi: 10.1038/s41467-021-22883-w.
Developing molecules that emulate the properties of naturally occurring ice-binding proteins (IBPs) is a daunting challenge. Rather than relying on the (limited) existing structure-property relationships that have been established for IBPs, here we report the use of phage display for the identification of short peptide mimics of IBPs. To this end, an ice-affinity selection protocol is developed, which enables the selection of a cyclic ice-binding peptide containing just 14 amino acids. Mutational analysis identifies three residues, Asp8, Thr10 and Thr14, which are found to be essential for ice binding. Molecular dynamics simulations reveal that the side chain of Thr10 hydrophobically binds to ice revealing a potential mechanism. To demonstrate the biotechnological potential of this peptide, it is expressed as a fusion ('Ice-Tag') with mCherry and used to purify proteins directly from cell lysate.
开发模拟天然冰结合蛋白（IBP）特性的分子是一项艰巨的挑战。我们没有依赖于已经为 IBP 建立的（有限的）现有结构-性质关系，而是在这里报告了使用噬菌体展示来鉴定 IBP 的短肽模拟物。为此，开发了一种冰亲和力选择方案，该方案能够选择仅包含 14 个氨基酸的环状冰结合肽。突变分析确定了三个残基，天冬氨酸 8（Asp8）、苏氨酸 10（Thr10）和苏氨酸 14（Thr14），它们被发现对冰结合至关重要。分子动力学模拟表明，Thr10 的侧链疏水性结合到冰上，揭示了一种潜在的机制。为了展示该肽的生物技术潜力，它被表达为与 mCherry 的融合物（“Ice-Tag”），并直接从细胞裂解物中用于纯化蛋白质。
