1k46
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Crystal Structure of the Type III Secretory Domain of Yersinia YopH Reveals a Domain-Swapped Dimer
OverviewOverview
Pathogenic strains of Yersinia deploy a type III secretion system to, inject the potent tyrosine phosphatase YopH into host cells, where it, dephosphorylates focal adhesion-associated substrates. The amino-terminal, non-catalytic domain of YopH is bifunctional; it is essential for the, secretion and binding of the specific chaperone SycH, but also targets the, catalytic domain to substrates in the infected cell. We describe the 2.2 A, resolution crystal structure of residues 1-129 of YopH from Yersinia, pseudotuberculosis. The amino-terminal alpha-helix (2-17), comprising the, secretion signal, and beta-strand (24-28) of one molecule exchange with, another molecule to form a domain-swapped dimer. Nuclear magnetic, resonance (NMR) and gel filtration experiments demonstrated that, YopH(1-129) could exist as a monomer and/or a dimer in solution. The, topology of the dimer and the dynamics of a monomeric form in solution, observed by NMR imply that YopH has the propensity to unfold partially., The dimer is probably not important physiologically, but may mimic how, SycH binds to the exposed non-polar surfaces of a partially unfolded YopH., Phosphopeptide-induced perturbations in NMR chemical shifts define a, substrate-binding surface on YopH(1-129) that includes residues previously, shown by mutagenesis to be essential for YopH function.
About this StructureAbout this Structure
1K46 is a Single protein structure of sequence from Yersinia pseudotuberculosis. Active as Protein-tyrosine-phosphatase, with EC number 3.1.3.48 Full crystallographic information is available from OCA.
ReferenceReference
Structure of the type III secretion and substrate-binding domain of Yersinia YopH phosphatase., Smith CL, Khandelwal P, Keliikuli K, Zuiderweg ER, Saper MA, Mol Microbiol. 2001 Nov;42(4):967-79. PMID:11737640
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