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Updated: Nov 21, 2025

Author Spotlight: A Computational Approach to Decipher Amino Acid Preferences in Multispecific Protein-Protein Interactions
Published on: January 26, 2024
Structural insights into a new substrate binding mode of a histidine acid phosphatase from Legionella pneumophila
Yu Guo1, Dan Zhou2, Hui Zhang1
1School of Life Sciences, Anhui Medical University, Hefei, Anhui, 230032, People's Republic of China.
Abstract:
MapA is a histidine acid phosphatase (HAP) from Legionella pneumophila that catalyzes the hydroxylation of a phosphoryl group from phosphomonoesters by an active-site histidine. Several structures of HAPs, including MapA, in complex with the inhibitor tartrate have been solved and the substrate binding tunnel identified; however, the substrate recognition mechanism remains unknown. To gain insight into the mechanism of substrate recognition, the crystal structures of apo-MapA and the MapAD281A mutant in complex with 5'-AMP were solved at 2.2 and 2.6 Å resolution, respectively. The structure of the MapAD281A/5'-AMP complex reveals that the 5'-AMP fits fully into the substrate binding tunnel, with the 2'-hydroxyl group of the ribose moiety stabilized by Glu201 and the adenine moiety sandwiched between His205 and Phe237. This is the second structure of a HAP/AMP complex solved with 5'-AMP binding in a unique manner in the active site. The structure presents a new substrate recognition mechanism of HAPs.
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