Department of Chemistry, University of British Columbia , Vancouver, British Columbia V6T 1Z1, Canada.
State Key Laboratory of Organic-Inorganic Composite Materials, Beijing University of Chemical Technology , Beijing 100029, P. R. China.
Biomacromolecules. 2017 Nov 13;18(11):3726-3732. doi: 10.1021/acs.biomac.7b01369. Epub 2017 Oct 9.
Protein hydrogels constructed from recombinant proteins have attracted increasing interests for fundamental biological studies as well as applications in biomedical engineering field. In such protein hydrogels, biochemical and physical properties of protein hydrogels are often coupled to each other, making it challenging to investigate the individual effect of chemical and physical cues on cells. Moreover, laborious engineering is often required to incorporate different protein ligands into such hydrogels. To address these challenges, functionalizing a blank slate protein hydrogel is an attractive approach. However, conjugating ligands to such a blank slate protein hydrogel is challenging, as existing bioconjugation methods developed in synthetic polymer hydrogels cannot be readily adapted for protein hydrogels, significantly impeding the use of this approach in the field. Here we report a facile, general, and robust method, which is based on the SpyCatcher-SpyTag chemistry, to covalently functionalize the "blank slate" of protein hydrogels using genetically encoded interacting partners. We demonstrate that this novel method enables covalent conjugation of a wide variety of ligands, including full-length intact folded proteins, to a blank slate protein hydrogel, and allows for the decoupling of biochemical and physical properties of hydrogels from each other and investigating the individual effect of biochemical and mechanical cues on cell behaviors. To our best knowledge, this is the first general approach enabling functionalization of protein hydrogels, and we anticipate that this novel approach will find a broad range of uses in protein-based biomaterials for applications in biomedical engineering.
由重组蛋白构建的蛋白质水凝胶因其在基础生物学研究以及生物医学工程领域的应用而受到越来越多的关注。在这种蛋白质水凝胶中，蛋白质水凝胶的生化和物理性质通常相互耦合，使得很难研究化学和物理线索对细胞的单独影响。此外，通常需要进行艰苦的工程设计才能将不同的蛋白质配体纳入此类水凝胶中。为了解决这些挑战，对空白蛋白质水凝胶进行功能化是一种有吸引力的方法。然而，将配体偶联到这种空白蛋白质水凝胶具有挑战性，因为在合成聚合物水凝胶中开发的现有生物偶联方法不能轻易适用于蛋白质水凝胶，这极大地阻碍了该方法在该领域的应用。在这里，我们报告了一种简便、通用且强大的方法，该方法基于 SpyCatcher-SpyTag 化学，使用遗传编码的相互作用伙伴共价修饰蛋白质水凝胶的“空白”。我们证明，这种新方法能够将各种配体（包括全长完整折叠的蛋白质）共价偶联到空白蛋白质水凝胶上，并允许将水凝胶的生化和物理性质彼此解耦，并研究生化和机械线索对细胞行为的单独影响。据我们所知，这是第一种能够对蛋白质水凝胶进行功能化的通用方法，我们预计这种新方法将在生物医学工程应用的基于蛋白质的生物材料中得到广泛应用。
