Designing heterodimeric two-stranded α-helical coiled-coils:: the effect of chain length on protein folding, stability and specificity
Designing heterodimeric two-stranded α-helical coiled-coils:: the effect of chain length on protein folding, stability and specificity
复制标题
DOI：
10.1034/j.1399-3011.2001.10972.x
复制
发表时间：
2001-12-01
期刊：
影响因子：
--
通讯作者：
Hodges, RS
中科院分区：
文献类型：
--
作者：
Litowski, JR;Hodges, RS
E/K 线圈是一种异二聚体卷曲线圈，被设计为通用肽捕获和递送系统，用于生物传感器和亲和色谱等应用。在此设计中，异二聚体的形成是通过在七肽重复序列的 e 和 9 位置放置带电残基来确定的。 E/K 螺旋的亲和力和稳定性已被修改，以便通过改变链长度来允许更大范围的缔合和解离条件，以获得三个、四个和五个七元卷曲螺旋（每条多肽链 21、28 和 35 个残基）。通过圆二色光谱、盐酸胍变性和氧化还原平衡实验检查链长对稳定性和折叠的影响。研究发现，链长的增加会增加异二聚体卷曲螺旋的稳定性，但是以非线性的方式。所得的二硫键异链分子和还原异二聚体具有广泛的稳定性（DeltaG=3.3-11.9 kcal/mol），极大地扩展了它们在蛋白质工程和生物医学应用中的使用范围。
The E/K coil, a heterodimeric coiled-coil, has been designed as a universal peptide capture and delivery system for use in applications such as biosensors and affinity chromatography. In this design, heterodimer formation is specified through the placement of charged residues at the e and 9 positions of the heptad repeat. The affinity and stability of the E/K coil has been modified in order to allow a greater range of conditions for association and dissociation by varying the chain length to obtain three, four and five heptad coiled-coils (21, 28 and 35 residues per polypeptide chain). The effect of chain length on stability and folding was examined by circular dichroism spectroscopy, guanidine hydrochloride denaturation, and redox equilibrium experiments. It was found that increases in chain length produced increases in the stability of heterodimeric coiled-coils but in a nonlinear, fashion. The resulting disulfide-bridged heterostranded molecules and reduced heterodimers span a wide range of stabilities (DeltaG=3.3-11.9 kcal/mol), greatly expanding their scope for use in protein engineering and biomedical applications.