Ye Yiming, Shealy Sarah, Lee Hsiau-Wei, Torshin Ivan, Harrison Robert, Yang Jenny J
Department of Chemistry, Center of Drug Design, Georgia State University, Atlanta, GA 30303, USA.
Protein Eng. 2003 Jun;16(6):429-34. doi: 10.1093/protein/gzg051.
The EF-hand calcium-binding loop III from calmodulin was inserted with glycine linkers into the scaffold protein CD2.D1 at three locations to study site-specific calcium binding properties of EF-hand motifs. After insertion, the host protein retains its native structure and forms a 1:1 metal-protein complex for calcium and its analog, lanthanum. Tyrosine-sensitized Tb3+ energy transfer exhibits metal binding and La3+ and Ca2+ compete for the metal binding site. The grafted EF-loop III in different environments has similar La3+ binding affinities, suggesting that it is largely solvated and functions independently from the host protein.
将来自钙调蛋白的EF手型钙结合环III通过甘氨酸接头插入支架蛋白CD2.D1的三个位置，以研究EF手型基序的位点特异性钙结合特性。插入后，宿主蛋白保留其天然结构，并与钙及其类似物镧形成1:1的金属-蛋白复合物。酪氨酸敏化的Tb3+能量转移显示出金属结合，并且La3+和Ca2+竞争金属结合位点。在不同环境中的嫁接EF环III具有相似的La3+结合亲和力，这表明它在很大程度上被溶剂化，并且独立于宿主蛋白发挥作用。
