Abstract In this work, the effect of trehalose was investigated on the structural stability of the d -Lactate dehydrogenase (DLDH) enzyme. Initially, response surface methodology (RSM) was applied to optimize different process variables for the stabilization of DLDH using trehalose. The stabilization of DLDH with trehalose was examined under various experimental conditions, including trehalose concentration, pH, temperature, and incubation time. The effect of the processing parameters was tested using the RSM method and a central composite design (CCD) model. According to the ANOVA results, there was a close correlation between the predicted and experimental values of the response parameter. The optimum values of trehalose concentration, pH, temperature, and incubation time were found to be 1.25 M, 8, 30 °C, and 25 min, respectively, for achieving the maximum activity. Then, the kinetic and thermodynamic parameters of DLDH in the absence and presence of trehalose were examined. The DLDH half-life at 40 °C was 28.88 min, while, in the presence of trehalose, the enzyme had a longer half-life (33.01 min) at this temperature. Also, in the end, molecular dynamics (MD) simulations of the DLDH enzyme was performed at the optimum conditions to obtain fundamental insights into the conformational transitions of the DLDH enzyme in the absence and presence of trehalose.

中文翻译：

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用海藻糖稳定重组D-乳酸脱氢酶：响应面方法和分子动力学模拟研究

摘要 在这项工作中，研究了海藻糖对 d-乳酸脱氢酶 (DLDH) 酶结构稳定性的影响。最初，响应面方法 (RSM) 用于优化不同的工艺变量，以使用海藻糖稳定 DLDH。在各种实验条件下检查了海藻糖对 DLDH 的稳定性，包括海藻糖浓度、pH、温度和孵育时间。使用 RSM 方法和中心复合设计 (CCD) 模型测试处理参数的影响。根据方差分析结果，响应参数的预测值和实验值之间存在密切的相关性。海藻糖浓度、pH、温度和孵育时间的最佳值分别为1.25 M、8、30°C和25分钟，以达到最大的活性。然后，检查了在海藻糖不存在和存在的情况下 DLDH 的动力学和热力学参数。DLDH 在 40 °C 下的半衰期为 28.88 分钟，而在海藻糖存在的情况下，该酶在此温度下的半衰期更长（33.01 分钟）。此外，最后，DLDH 酶的分子动力学 (MD) 模拟在最佳条件下进行，以获得对 DLDH 酶在海藻糖不存在和存在下的构象转变的基本见解。