2hw4

Publication Abstract from PubMed

Phosphatases are a diverse group of enzymes that regulate numerous cellular processes. Much of what is known relates to the tyrosine, threonine, and serine phosphatases, whereas the histidine phosphatases have not been studied as much. The structure of phosphohistidine phosphatase (PHPT1), the first identified eukaryotic-protein histidine phosphatase, has been determined to a resolution of 1.9A using multiple-wavelength anomalous dispersion methods. This enzyme can dephosphorylate a variety of proteins (e.g. ATP-citrate lyase and the beta-subunit of G proteins). A putative active site has been identified by its electrostatic character, ion binding, and conserved protein residues. Histidine 53 is proposed to play a major role in histidine dephosphorylation based on these observations and previous mutational studies. Models of peptide binding are discussed to suggest possible mechanisms for substrate recognition.

First structure of a eukaryotic phosphohistidine phosphatase.,Busam RD, Thorsell AG, Flores A, Hammarstrom M, Persson C, Hallberg BM J Biol Chem. 2006 Nov 10;281(45):33830-4. Epub 2006 Sep 21. PMID:16990267^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.