Elias James Corey Institute of Biomedical Research, Wuxi Biortus Biosciences Co., Ltd , Jiangyin, 214437, China.
J Am Chem Soc. 2015 Dec 16;137(49):15358-61. doi: 10.1021/jacs.5b09895. Epub 2015 Dec 4.
The coordination bond between gold and sulfur (Au-S) has been widely studied and utilized in many fields. However, detailed investigations on the basic nature of this bond are still lacking. A gold-specific binding protein, GolB, was recently identified, providing a unique opportunity for the study of the Au-S bond at the molecular level. We probed the mechanical strength of the gold-sulfur bond in GolB using single-molecule force spectroscopy. We measured the rupture force of the Au-S bond to be 165 pN, much lower than Au-S bonds measured on different gold surfaces (∼1000 pN). We further solved the structures of apo-GolB and Au(I)-GolB complex using X-ray crystallography. These structures showed that the average Au-S bond length in GolB is much longer than the reported average value of Au-S bonds. Our results highlight the dramatic influence of the unique biological environment on the stability and strength of metal coordination bonds in proteins.
金与硫之间的配位键（Au-S）已得到广泛研究，并在许多领域得到应用。然而，对于这种键的基本性质的详细研究仍然缺乏。最近发现了一种特定于金的结合蛋白 GolB，为在分子水平上研究 Au-S 键提供了独特的机会。我们使用单分子力谱技术探测了 GolB 中硫-金键的机械强度。我们测量的 Au-S 键的断裂力为 165 pN，远低于在不同金表面测量的 Au-S 键（约 1000 pN）。我们进一步使用 X 射线晶体学解析了apo-GolB 和 Au（I）-GolB 复合物的结构。这些结构表明，GolB 中的平均 Au-S 键长比报道的 Au-S 键的平均长度要长得多。我们的结果强调了独特的生物环境对蛋白质中金属配位键的稳定性和强度的巨大影响。
