Effect of histidine protonation state on ligand binding at the ATP-binding site of human protein kinase CK2.

ABSTRACT: Histidine residues contribute to numerous molecular interactions, owing to their structure with the ionizable aromatic side chain with pK_a close to the physiological pH. Herein, we studied how the two histidine residues, His115 and His160 of the catalytic subunit of human protein kinase CK2, affect the binding of the halogenated heterocyclic ligands at the ATP-binding site. Thermodynamic studies on the interaction between five variants of hCK2α (WT protein and four histidine mutants) and three ionizable bromo-benzotriazoles and their conditionally non-ionizable benzimidazole counterparts were performed with nanoDSF, MST, and ITC. The results allowed us to identify the contribution of interactions involving the particular histidine residues to ligand binding. We showed that despi

SUBMITTER: Winiewska-Szajewska M 

PROVIDER: S-EPMC10794401 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature