Sproß Jens, Yamashita Yasunobu, Gröger Harald
Chair of Industrial Organic Chemistry and Biotechnology, Faculty of Chemistry, Bielefeld University, Universitätsstrasse25, 33615, Bielefeld, Germany.
Chembiochem. 2020 Jul 16;21(14):1968-1971. doi: 10.1002/cbic.201900648. Epub 2020 Mar 5.
Ion mobility spectrometry (IMS) coupled with mass spectrometry (MS) enables the investigation of protein folding in solution. Herein, a proof-of-concept for obtaining structural information about the folding of a protein in dependency of the amount of an organic cosolvent in the aqueous medium by means of this IMS-MS method is presented. By analyzing the protein with native nano-electrospray ionization IMS-MS, the impact of acetonitrile as a representative organic cosolvent and/or pH values on the folding of an enzyme was successfully evaluated in a fast and straightforward fashion, as exemplified for an ene reductase from Gluconobacter oxydans. The IMS-MS results are in agreement with findings from the nicotinamide adenine dinucleotide phosphate (NADPH)-based spectrophotometric enzyme activity tests under analogous conditions, and thus, also rationalizing these "wet" analytical data. For this ene reductase, a higher tolerance against CH CN in the presence of a buffer was observed by both analytical methods. The results suggest that this IMS-MS methodology could be a useful complementary tool to existing methods in process optimization and fine-tuning of solvent conditions for biotransformations.
离子迁移谱（IMS）与质谱（MS）联用能够研究溶液中的蛋白质折叠。本文展示了一种概念验证，即通过这种IMS-MS方法，获取关于蛋白质在水介质中折叠结构信息与有机助溶剂含量之间的依赖关系。通过使用原生纳米电喷雾电离IMS-MS分析蛋白质，以氧化葡萄糖酸杆菌的烯还原酶为例，快速且直接地成功评估了作为代表性有机助溶剂的乙腈和/或pH值对一种酶折叠的影响。IMS-MS结果与在类似条件下基于烟酰胺腺嘌呤二核苷酸磷酸（NADPH）的分光光度法酶活性测试结果一致，从而也使这些“湿”分析数据合理化。对于这种烯还原酶，两种分析方法均观察到在缓冲液存在下其对CH CN具有更高的耐受性。结果表明，这种IMS-MS方法可能是现有方法在生物转化溶剂条件的工艺优化和微调方面有用的补充工具。
