3CVR

Crystal structure of the full length IpaH3

Summary for 3CVR

• Entry DOI: 10.2210/pdb3cvr/pdb
• Descriptor: Invasion plasmid antigen (2 entities in total)
• Functional Keywords: leucine rich repeat and alpha fold, ligase
• Biological source: Shigella flexneri 2a
• Cellular location: Secreted (By similarity): Q83RJ4
• Total number of polymer chains: 1
• Total formula weight: 65508.30

Authors

Zhu, Y.,Shao, F. (deposition date: 2008-04-19, release date: 2008-11-11, Last modification date: 2024-10-30)

Primary citation

Zhu, Y.,Li, H.,Hu, L.,Wang, J.,Zhou, Y.,Pang, Z.,Liu, L.,Shao, F.
Structure of a Shigella effector reveals a new class of ubiquitin ligases
Nat.Struct.Mol.Biol., 15:1302-1308, 2008

PubMed Abstract: Bacterial pathogens have evolved effector proteins with ubiquitin E3 ligase activities through structural mimicking. Here we report the crystal structure of the Shigella flexneri type III effector IpaH3, a member of the leucine-rich repeat (LRR)-containing bacterial E3 family. The LRR domain is structurally similar to Yersinia pestis YopM and potentially binds to substrates. The structure of the C-terminal E3 domain differs from the typical RING- and HECT-type E3s. IpaH3 synthesizes a Lys48-linked ubiquitin chain, and the reaction requires noncovalent binding between ubiquitin and a specific E2, UbcH5. Free ubiquitin serves as an acceptor for IpaH3-catalyzed ubiquitin transfer. Cys363 within a conserved CXD motif acts as a nucleophile to catalyze ubiquitin transfer through a transthiolation reaction. The D365N mutant is devoid of E3 activities but turns into a potent ubiquitin-E2 thioesterase. Our analysis establishes a structurally and mechanistically distinct class of ubiquitin ligases found exclusively in pathogenic or symbiotic bacteria.

PubMed: 18997779
DOI: 10.1038/nsmb.1517

Experimental method

X-RAY DIFFRACTION (2.8 Å)