Messerle B A, Bos M, Schäffer A, Vasák M, Kägi J H, Wüthrich K
Institut für Molecularbiologie un Biophysik, Eidgenössische Technische Hochschule-Hönggerberg, Zürich, Switzerland.
J Mol Biol. 1990 Aug 5;214(3):781-6. doi: 10.1016/0022-2836(90)90292-T.
In human metallothionein-2, the exchange rate constants of ten amide protons were found to range from 1.7 x 10(-4) to 1 x 10(-1) min-1 at pH 6.3 and 8 degrees C. Most of these slowly exchanging protons could be associated with hydrogen bonds in secondary structure elements of the alpha-domain. Amide proton exchange rates thus present an additional criterion for the structural characterization of different metallothioneins, which could be particularly valuable for comparisons of different homologous protein preparations containing nuclear magnetic resonance-inactive metal ions, where the metal-polypeptide co-ordinative bonds cannot be identified directly.
在人金属硫蛋白-2中，发现在pH 6.3和8℃条件下，十个酰胺质子的交换速率常数范围为1.7×10⁻⁴至1×10⁻¹ min⁻¹。这些缓慢交换的质子大多可能与α结构域二级结构元件中的氢键有关。因此，酰胺质子交换速率为不同金属硫蛋白的结构表征提供了一个额外的标准，这对于比较含有核磁共振惰性金属离子的不同同源蛋白质制剂可能特别有价值，因为在这些制剂中金属-多肽配位键无法直接识别。
