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Updated: Oct 17, 2025

Author Spotlight: A Computational Approach to Decipher Amino Acid Preferences in Multispecific Protein-Protein Interactions
Published on: January 26, 2024
Role of active site arginine residues in substrate recognition by PPM1A
Itsumi Tani1, Shogo Ito1, Yukiko Shirahata1
1Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan.
Abstract:
Reversible protein phosphorylation is a key mechanism for regulating numerous cellular events. The metal-dependent protein phosphatases (PPM) are a family of Ser/Thr phosphatases, which uniquely recognize their substrate as a monomeric enzyme. In the case of PPM1A, it has the capacity to dephosphorylate a variety of substrates containing different sequences, but it is not yet fully understood how it recognizes its substrates. Here we analyzed the role of Arg33 and Arg186, two residues near the active site, on the dephosphorylation activity of PPM1A. The results showed that both Arg residues were critical for enzymatic activity and docking-model analysis revealed that Arg186 is positioned to interact with the substrate phosphate group. In addition, our results suggest that which Arg residue plays a more significant role in the catalysis depends directly on the substrate.
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