Hydrogen-Deuterium Exchange Rate between a Peptide Group and an Aqueous Solvent as Determined by a Stopped-Flow Ultraviolet Spectrophotometry
Hydrogen-Deuterium Exchange Rate between a Peptide Group and an Aqueous Solvent as Determined by a Stopped-Flow Ultraviolet Spectrophotometry
复制标题
通过停流紫外分光光度法测定肽基团和水性溶剂之间的氢-氘交换率
DOI：
--
复制
发表时间：
1978
期刊：
影响因子：
--
通讯作者：
M. Tsuboi
中科院分区：
文献类型：
--
作者：
Tetsuo Takahashi;M. Nakanishi;M. Tsuboi
当N-甲基乙酰胺的1H 2 O溶液与2 H2O快速混合时，观察到227 nm处的紫外吸光度随时间而降低。N，N-二甲基乙酰胺的情况并非如此。因此，吸光度的时间依赖性降低归因于N-甲基乙酰胺的氘化（NH→ND）反应。这提供了用于测定多肽或蛋白质中肽基团的氘化率的适当方法。在pH=5-8和温度=10-40 ℃范围内，用这种方法测定了聚-D，L-丙氨酸的氘代速率。在此范围内，氘化反应总是以单一的一级反应进行，速率常数ke在实验误差范围内表示为ke=6.4×10（6+pH−3850 <$T）这是用来估算速率常数为kj的蛋白质分子中给定肽基（j）的衰减因子γj=kj <$ke的标准速率常数值。
When an 1H2O solution of N-methylacetamide was rapidly mixed with 2H2O, a time-dependent decrease of the ultraviolet absorbance at 227 nm was observed. This was not the case with N,N-dimethylacetamide. Hence, the time-dependent decrease in absorbance was attributed to be caused by the deuteration (NH→ND) reaction of N-methylacetamide. This provides an appropriate method for determining deuteration rate of the peptide group in a polypeptide or in a protein. By this method the deuteration rate of poly-D,L-alanine has been examined in the pH=5—8 and temperature=10—40 °C range. In this range, the deuteration was found to proceed always as a single first-order reaction, and the rate constant ke is expressed within an experimental error as ke=6.4×10(6+pH−3850⁄T) This is to be used as a standard rate-constant value in estimating the attenuation factor γj=kj⁄ke of a given peptide group (j) in a protein molecule whose rate constant value is kj.