PDBsum entry: 1z13

Hydrolase

PDB id: 1z13

Contents

Protein chain

157 a.a. *

Ligands

MOO

* Residue conservation analysis

PDB id:

1z13

Name:

Hydrolase

Title:

Crystal structure of bovine low molecular weight ptpase comp molybdate

Structure:

Low molecular weight phosphotyrosine protein phos chain: a. Synonym: low molecular weight cytosolic acid phosphatase, p engineered: yes

Source:

Bos taurus. Cattle. Organism_taxid: 9913. Gene: acp1. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

2.20Å R-factor: 0.159

Authors:

M.Zhang,M.Zhou,R.L.Van Etten,C.V.Stauffacher

Key ref:

M.Zhang et al. (1997). Crystal structure of bovine low molecular weight phosphotyrosyl phosphatase complexed with the transition state analog vanadate. Biochemistry, 36, 15-23. PubMed id: 8993313 DOI: 10.1021/bi961804n

Date:

03-Mar-05 Release date: 05-Apr-05

Protein chain

P11064  (PPAC_BOVIN) -  Low molecular weight phosphotyrosine protein phosphatase

Seq: 158 a.a.

Struc: 157 a.a.

Enzyme reactions

• Enzyme class 2: E.C.3.1.3.2 - Acid phosphatase.
• Reaction: A phosphate monoester + H₂O = an alcohol + phosphate
• Enzyme class 3: E.C.3.1.3.48 - Protein-tyrosine-phosphatase.
• Reaction: Protein tyrosine phosphate + H₂O = protein tyrosine + phosphate

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/bi961804n

Biochemistry 36:15-23 (1997)

PubMed id: 8993313

Crystal structure of bovine low molecular weight phosphotyrosyl phosphatase complexed with the transition state analog vanadate.

M.Zhang, M.Zhou, R.L.Van Etten, C.V.Stauffacher.

ABSTRACT

The early transition metal oxoanions vanadate, molybdate, and tungstate are widely used inhibitors for phosphatase enzymes. These oxoanions could inhibit such enzymes by simply mimicking the tetrahedral geometry of phosphate ion. However, in some cases, the enzyme-inhibitor dissociation constants (Ki) for these oxoanions are much lower than that for phosphate. Such observations gave rise to the hypothesis that in some cases these transition metal oxoanions may inhibit phosphomonoesterases by forming complexes that resemble the trigonal bipyramidal geometry of the SN2(P) transition state. As a test of this, the crystal structures of a low molecular weight protein tyrosine phosphatase at pH 7.5 complexed with the inhibitors vanadate and molybdate were solved at 2.2 A resolution and compared to a newly refined 1.9 A structure of the enzyme. Geometric restraints on the oxoanions were relaxed during refinement in order to minimize model bias. Both inhibitors were bound at the active site, and the overall protein structures were left unchanged, although some small but significant side chain movements at the active site were observed. Vanadate ion formed a covalent linkage with the nucleophile Cys12 at the active site and exhibited a trigonal bipyramidal geometry. In contrast, simple tetrahedral geometry was observed for the weaker molybdate complex. These studies are consistent with the conclusion that vanadate inhibits tyrosine phosphatases by acting as a transition state analog. The structure of the vanadate complex may be expected to closely resemble the transition state for reactions catalyzed by protein tyrosine phosphatases.