3CKD

Crystal structure of the C-terminal domain of the Shigella type III effector IpaH

Summary for 3CKD

• Entry DOI: 10.2210/pdb3ckd/pdb
• Descriptor: Invasion plasmid antigen, secreted by the Mxi-Spa secretion machinery, SULFATE ION, GLYCEROL, ... (5 entities in total)
• Functional Keywords: e3 ubiquitin ligase, helical, type iii effector, structural genomics, psi-2, protein structure initiative, midwest center for structural genomics, mcsg, ligase
• Biological source: Shigella flexneri 2a str. 301
• Total number of polymer chains: 3
• Total formula weight: 107498.46

Authors

Lam, R.,Singer, A.U.,Cuff, M.E.,Skarina, T.,Kagan, O.,DiLeo, R.,Edwards, A.M.,Joachimiak, A.,Savchenko, A.,Midwest Center for Structural Genomics (MCSG) (deposition date: 2008-03-14, release date: 2008-03-25, Last modification date: 2024-11-20)

Primary citation

Singer, A.U.,Rohde, J.R.,Lam, R.,Skarina, T.,Kagan, O.,Dileo, R.,Chirgadze, N.Y.,Cuff, M.E.,Joachimiak, A.,Tyers, M.,Sansonetti, P.J.,Parsot, C.,Savchenko, A.
Structure of the Shigella T3SS effector IpaH defines a new class of E3 ubiquitin ligases.
Nat.Struct.Mol.Biol., 15:1293-1301, 2008

PubMed Abstract: IpaH proteins are E3 ubiquitin ligases delivered by the type III secretion apparatus into host cells upon infection of humans by the Gram-negative pathogen Shigella flexneri. These proteins comprise a variable leucine-rich repeat-containing N-terminal domain and a conserved C-terminal domain harboring an invariant cysteine residue that is crucial for activity. IpaH homologs are encoded by diverse animal and plant pathogens. Here we demonstrate that the IpaH C-terminal domain carries the catalytic activity for ubiquitin transfer and that the N-terminal domain carries the substrate specificity. The structure of the IpaH C-terminal domain, determined to 2.65-A resolution, represents an all-helical fold bearing no resemblance to previously defined E3 ubiquitin ligases. The conserved and essential cysteine residue lies on a flexible, surface-exposed loop surrounded by conserved acidic residues, two of which are crucial for IpaH activity.

PubMed: 18997778
DOI: 10.1038/nsmb.1511

Experimental method

X-RAY DIFFRACTION (2.65 Å)