4oko

Crystal structure of Francisella tularensis REP34 (Rapid Encystment Phenotype Protein 34 KDa)Crystal structure of Francisella tularensis REP34 (Rapid Encystment Phenotype Protein 34 KDa)

Structural highlights 4oko is a 4 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: , Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Publication Abstract from PubMed Francisella tularensis is the etiological agent of tularemia, or rabbit fever. While F. tularensis is a recognized biothreat agent with broad and expanding geographical range, its mechanism of infection and environmental persistence remain poorly understood. Previously, we identified seven F. tularensis proteins that induce a rapid encystment phenotype (REP) in the free-living amoeba, Acanthamoeba castellanii. Encystment is essential to the pathogen's long-term intracellular survival in amoeba. Here, we characterize the cellular and molecular function of REP34, a REP protein of mass 34 kDa. A REP34 knockout strain of F. tularensis has a reduced ability to both induce encystment in A. castellanii and invade human macrophages. We determined the crystal structure of REP34 to 2.05-A resolution and demonstrate robust carboxypeptidase B-like activity for the enzyme. REP34 is a zinc-containing monomeric protein with close structural homology to the metallocarboxypeptidase family of peptidases. REP34 possesses a novel topology and substrate binding pocket that deviates from the canonical funnelin structure of carboxypeptidases, putatively resulting in a catalytic role for a conserved tyrosine and distinct S1' recognition site. Taken together, these results identify REP34 as an active carboxypeptidase, implicate the enzyme as a potential key F. tularensis effector protein, and may help elucidate a mechanistic understanding of F. tularensis infection of phagocytic cells. Structure and function of REP34 implicates carboxypeptidase activity in Francisella tularensis host-cell invasion.,Feld GK, El-Etr S, Corzett MH, Hunter MS, Belhocine K, Monack DM, Frank M, Segelke BW, Rasley A J Biol Chem. 2014 Sep 17. pii: jbc.M114.599381. PMID:25231992 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 4oko, resolution 2.05Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image