1glc
CATION PROMOTED ASSOCIATION (CPA) OF A REGULATORY AND TARGET PROTEIN IS CONTROLLED BY PHOSPHORYLATION
|
OverviewOverview
A central question in molecular biology concerns the means by which a, regulatory protein recognizes different targets. IIIGlc, the, glucose-specific phosphocarrier protein of the bacterial, phosphotransferase system, is also the central regulatory element of the, PTS. Binding of unphosphorylated IIIGlc inhibits several non-PTS proteins, but there is little or no sequence similarity between IIIGlc binding sites, on different target proteins. The crystal structure of Escherichia coli, IIIGlc bound to one of its regulatory targets, glycerol kinase, has been, refined at 2.6-A resolution in the presence of products, adenosine, diphosphate and glycerol 3-phosphate. Structural and kinetic analyses show, that the complex of IIIGlc with glycerol kinase creates an intermolecular, Zn(II) binding site with ligation identical to that of the zinc peptidase, thermolysin. The zinc is coordinated by the two active-site histidines of, IIIGlc, a glutamate of glycerol kinase, and a water molecule. Zn(II) at, 0.01 and 0.1 mM decreases the Ki of IIIGlc for glycerol kinase by factors, of about 15 and 60, respectively. The phosphorylation of one of the, histidines of IIIGlc, in its alternative role as phosphocarrier, provides, an elegant means of controlling the cation-enhanced protein-protein, regulatory interaction. The need for the target protein to supply only one, metal ligand may account for the lack of sequence similarity among the, regulatory targets of IIIGlc.
About this StructureAbout this Structure
1GLC is a Protein complex structure of sequences from Escherichia coli with MG, ZN, G3H and ADP as ligands. Active as Protein-N(pi)-phosphohistidine--sugar phosphotransferase, with EC number 2.7.1.69 Full crystallographic information is available from OCA.
ReferenceReference
Cation-promoted association of a regulatory and target protein is controlled by protein phosphorylation., Feese M, Pettigrew DW, Meadow ND, Roseman S, Remington SJ, Proc Natl Acad Sci U S A. 1994 Apr 26;91(9):3544-8. PMID:8170944
Page seeded by OCA on Tue Nov 20 16:08:34 2007