Hydrogen Bonding of β-Turn Structure Is Stabilized in D2O

作者：Younhee Cho, Laura Sagle, Satoshi Iimura, Yanjie Zhang, Jaibir Kherb, Ashutosh Chilkoti, J. Martin Scholtz, Paul S. Cremer · 发表于：Journal of the American Chemical Society · 年份：2009 · DOI：10.1021/ja9040785 · 被引用次数：95 · 研究领域：Connective tissue disorders research、Elasticity and Material Modeling、Nuclear Structure and Function

The lower critical solution temperature (LCST) of elastin-like polypeptides (ELPs) was investigated as a function of ELP chain length and guest residue chemistry. These measurements were made in both D(2)O and H(2)O. Differences in the LCST values with heavy and light water were correlated with secondary structure formation of the polypeptide chains. Such structural information was obtained by circular dichroism and infrared measurements. Additional thermodynamic data were obtained by differential scanning calorimetry. It was found that there is a greater change in the LCST value between H(2)O and D(2)O for those polypeptides which form the greatest amount of beta-turn/beta-aggregate structure. Moreover, these same molecules were the least hydrophobic ELPs. Therefore, hydrogen bonding rather than hydrophobicity was the key factor in the stabilization of the collapsed state of ELPs in D(2)O compared with H(2)O.