IMDEA Nanoscience, 28049 Madrid, Spain.
Departamento de Química Inorgánica, Facultad de Químicas, Universidad Complutense, 28040 Madrid, Spain.
Biomolecules. 2018 Mar 20;8(1):13. doi: 10.3390/biom8010013.
Acid proteins capable of nucleating Ca and displaying aggregation capacity play key roles in the formation of calcium carbonate biominerals. The helix-loop helix EF-hands are the most common Ca-binding motifs in proteins. Calcium is bound by the loop region. These motifs are found in many proteins that are regulated by calcium. Gad m 1, an Atlantic cod β-parvalbumin isoform, is a monomeric EF-hand protein that acts as a Ca buffer in fish muscle; the neutral and acid apo-forms of this protein can form amyloids. Since Ca-nucleating proteins have a propensity to form extended β-strand structures, we wondered whether amyloid assemblies of an EF-hand protein were able to influence calcium carbonate crystallization in vitro. Here, we used the Gad m 1 chain as a model to generate monomeric and amyloid assemblies and to analyze their effect on calcite formation in vitro. We found that only amyloid assemblies alter calcite morphology.
能够成核 Ca 并表现出聚集能力的酸性蛋白在碳酸钙生物矿化的形成中起着关键作用。螺旋环螺旋 EF 手是蛋白质中最常见的 Ca 结合基序。钙由环区结合。这些基序存在于许多受钙调节的蛋白质中。大西洋 cod β-副肌球蛋白同工型 Gad m 1 是一种单体 EF 手蛋白，在鱼类肌肉中作为钙缓冲剂；该蛋白的中性和酸性脱辅基形式可以形成淀粉样纤维。由于成核 Ca 的蛋白质有形成伸展的β-链结构的倾向，我们想知道 EF 手蛋白的淀粉样纤维组装是否能够影响体外碳酸钙结晶。在这里，我们使用 Gad m 1 链作为模型来产生单体和淀粉样纤维组装体，并分析它们对体外方解石形成的影响。我们发现只有淀粉样纤维组装体改变了方解石的形态。
