Craig Douglas B, Reinfelds Gundars, Henderson Anna
Chemistry Department, University of Winnipeg, Winnipeg, MB, Canada.
Electrophoresis. 2014 Aug;35(16):2408-11. doi: 10.1002/elps.201300526. Epub 2014 Mar 25.
Capillary electrophoresis has been used to demonstrate that individual molecules of a given enzyme support different catalytic rates. In order to determine how rate varies with temperature, and determine activation energies for individual β-galactosidase molecules, a 12-channel Peltier array temperature control device was constructed where the temperature of each cell was separately controlled. This array was used to control the temperature of the central 30 cm of a 50 cm long capillary, producing a temperature gradient along its length. Continuous flow single β-galactosidase molecule assays were performed allowing measurement of the catalytic rates at different temperatures. Arrhenius plots were produced and the distribution of activation energies for individual β-galactosidase molecules was found to be 56 ± 10 kJ/mol with a range of 34-72 kJ/mol.
毛细管电泳已被用于证明给定酶的单个分子具有不同的催化速率。为了确定速率如何随温度变化，并确定单个β-半乳糖苷酶分子的活化能，构建了一个12通道珀耳帖阵列温度控制装置，其中每个单元的温度是单独控制的。该阵列用于控制一根50厘米长毛细管中间30厘米的温度，沿其长度产生温度梯度。进行连续流动单个β-半乳糖苷酶分子测定，从而能够测量不同温度下的催化速率。绘制了阿累尼乌斯图，发现单个β-半乳糖苷酶分子的活化能分布为56±10千焦/摩尔，范围为34 - 72千焦/摩尔。
