Title : Crystal structures of human
prostatic acid phosphatase in complex with a phosphate ion and alpha-benzylaminobenzylphosphonic acid update the mechanistic picture and offer new insights into inhibitor design
Abstract :
- The X-ray crystal structure of human prostatic acid phosphatase ( PAP ) in complex with a phosphate ion has been determined at 2.4 A resolution
- This structure offers a snapshot of the final intermediate in the catalytic mechanism and does not support the role of Asp 258 as a proton donor in catalysis
- A total of eight hydrogen bonds serve to strongly bind the phosphate ion within the active site
- Bound PEG molecules from the crystallization matrix have allowed the identification of a channel within the molecule that likely plays a role in molecular recognition and in macromolecular substrate selectivity
- Additionally, the structure of PAP in complex with a phosphate derivative, alpha-benzylaminobenzylphosphonic acid, a potent inhibitor (IC(50) = 4 nM), has been determined to 2.9 A resolution
- This structure gives new insight into the determinants of binding hydrophobic ligands within the active site and allows us to explain PAP 's preference for aromatic substrates