西安交通大学汪方军团队报道了时间分辨紫外光解质谱探测突变诱导的蛋白质稳定性和展开动力学改变。相关研究成果发表在2024年3月20日出版的《美国化学会杂志》。

突变如何影响蛋白质的稳定性和结构动力学，对于理解病理过程和合理的药物设计至关重要。

该文中，研究人员通过快速混合毛细管装置建立了一个时间分辨天然质谱（TR-nMS）平台，用于监测酸引发的蛋白质展开过程。通过对结构信息性光片段的193nm紫外线光解（UVPD）分析，进一步描述了蛋白质结构展开中的分子细节。

与野生型二氢叶酸还原酶（WT-DHFR）相比，M42T/H114R突变体（MT-DHFR。对展开中间体和原始DHFR形式的UVPD比较表明，辅因子NADPH对DHFR结构具有特殊的稳定作用，M42T/H114R突变导致NADPH-DHFR相互作用显著减少，从而促进结构的展开。

该研究为探索突变诱导的药物靶标稳定性，和结构动力学的细微变化铺平了道路。

附：英文原文

Title: Time-Resolved Ultraviolet Photodissociation Mass Spectrometry Probes the Mutation-Induced Alterations in Protein Stability and Unfolding Dynamics

Author: Pan Luo, Zheyi Liu, Can Lai, Zhixiong Jin, Mengdie Wang, Heng Zhao, Yu Liu, Weiqing Zhang, Xingan Wang, Chunlei Xiao, Xueming Yang, Fangjun Wang

Issue&Volume: March 20, 2024

Abstract: How mutations impact protein stability and structure dynamics is crucial for understanding the pathological process and rational drug design. Herein, we establish a time-resolved native mass spectrometry (TR-nMS) platform via a rapid-mixing capillary apparatus for monitoring the acid-initiated protein unfolding process. The molecular details in protein structure unfolding are further profiled by a 193 nm ultraviolet photodissociation (UVPD) analysis of the structure-informative photofragments. Compared with the wild-type dihydrofolate reductase (WT-DHFR), the M42T/H114R mutant (MT-DHFR) exhibits a significant stability decrease in TR-nMS characterization. UVPD comparisons of the unfolding intermediates and original DHFR forms indicate the special stabilization effect of cofactor NADPH on DHFR structure, and the M42T/H114R mutations lead to a significant decrease in NADPH-DHFR interactions, thus promoting the structure unfolding. Our study paves the way for probing the mutation-induced subtle changes in the stability and structure dynamics of drug targets.

DOI: 10.1021/jacs.4c00316

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c00316