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Published on: December 5, 2019
Protocol for detecting histidine polyphosphate modification of human proteins via MBP-tagged expression in E. coli
Kirsten Lehotsky1, Nolan Neville1, Zongchao Jia1
1Department of Biomedical and Molecular Sciences, Queen's University, Kingston K7L 3N6, Canada.
None:
Polyphosphate exhibits a unique post-translational modification-like function, known as histidine polyphosphate modification (HPM), marked by a robust non-covalent interaction with histidine repeat proteins. Here, we present a protocol for detecting HPM of human proteins via maltose-binding protein-tagged expression in E. coli. We describe steps for detecting HPM by observing electrophoretic mobility shifts on NuPAGE gels followed by western blot. We then detail procedures for analyzing the influence of ionic strength and pH on HPM. For complete details on the use and execution of this protocol, please refer to Neville et al.1.

