PDBsum entry: 1c0e

Hydrolase

PDB id: 1c0e

Contents

Protein chains

154 a.a. *

Ligands

PO4 ×2

Waters ×98

* Residue conservation analysis

PDB id:

1c0e

Name:

Hydrolase

Title:

Active site s19a mutant of bovine heart phosphotyrosyl phosphatase

Structure:

Protein (tyrosine phosphatase (orthophosphoric monoester phosphohydrolase)). Chain: a, b. Engineered: yes. Mutation: yes

Source:

Bos taurus. Cattle. Organism_taxid: 9913. Organ: heart. Expressed in: escherichia coli. Expression_system_taxid: 562

Biol. unit:

Dimer (from PQS)

Resolution:

2.20Å R-factor: 0.191 R-free: 0.244

Authors:

L.Tabernero,B.N.Evans,P.A.Tishmack,R.L.Van Etten, C.V.Stauffacher

Key ref:

L.Tabernero et al. (1999). The structure of the bovine protein tyrosine phosphatase dimer reveals a potential self-regulation mechanism. Biochemistry, 38, 11651-11658. PubMed id: 10512620 DOI: 10.1021/bi990381x

Date:

15-Jul-99 Release date: 28-Sep-99

Protein chains

P11064  (PPAC_BOVIN) -  Low molecular weight phosphotyrosine protein phosphatase

Seq: 158 a.a.

Struc: 154 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class 2: E.C.3.1.3.2 - Acid phosphatase.
• Reaction: A phosphate monoester + H₂O = an alcohol + phosphate

phosphate monoester + H(2)O = alcohol + phosphate (Bound ligand (Het Group name = PO4) corresponds exactly)

• Enzyme class 3: E.C.3.1.3.48 - Protein-tyrosine-phosphatase.
• Reaction: Protein tyrosine phosphate + H₂O = protein tyrosine + phosphate

Protein tyrosine phosphate + H(2)O = protein tyrosine + phosphate (Bound ligand (Het Group name = PO4) corresponds exactly)

Note, where more than one E.C. class is given (as above), each may correspond to a different protein domain or, in the case of polyprotein precursors, to a different mature protein.

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

 Gene Ontology (GO) functional annotation 

• Cellular component: cytoplasm (1 term)
• Biological process: protein amino acid dephosphorylation (1 term)
• Biochemical function: hydrolase activity (5 terms)

reference

DOI no: 10.1021/bi990381x

Biochemistry 38:11651-11658 (1999)

PubMed id: 10512620

The structure of the bovine protein tyrosine phosphatase dimer reveals a potential self-regulation mechanism.

L.Tabernero, B.N.Evans, P.A.Tishmack, R.L.Van Etten, C.V.Stauffacher.

ABSTRACT

The bovine protein tyrosine phosphatase (BPTP) is a member of the class of low-molecular weight protein tyrosine phosphatases (PTPases) found to be ubiquitous in mammalian cells. The catalytic site of BPTP contains a CX(5)R(S/T) phosphate-binding motif or P-loop (residues 12-19) which is the signature sequence for all PTPases. Ser19, the final residue of the P-loop motif, interacts with the catalytic Cys12 and participates in stabilizing the conformation of the active site through interactions with Asn15, also in the P-loop. Mutations at Ser19 result in an enzyme with altered kinetic properties with changes in the pK(a) of the neighboring His72. The X-ray structure of the S19A mutant enzyme shows that the general conformation of the P-loop is preserved. However, changes in the loop containing His72 result in a displacement of the His72 side chain that may explain the shift in the pK(a). In addition, it was found that in the crystal, the protein forms a dimer in which Tyr131 and Tyr132 from one monomer insert into the active site of the other monomer, suggesting a dual-tyrosine motif on target sites for this enzyme. Since the activity of this PTPase is reportedly regulated by phosphorylation at Tyr131 and Tyr132, the structure of this dimer may provide a model of a self-regulation mechanism for the low-molecular weight PTPases.