2p1h

Rapid Folding and Unfolding of Apaf-1 CARDRapid Folding and Unfolding of Apaf-1 CARD

Structural highlights 2p1h is a 1 chain structure with sequence from Homo sapiens. The September 2014 RCSB PDB Molecule of the Month feature on Apoptosomes by David Goodsell is 10.2210/rcsb_pdb/mom_2014_9. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.59Å Ligands: Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function APAF_HUMAN Oligomeric Apaf-1 mediates the cytochrome c-dependent autocatalytic activation of pro-caspase-9 (Apaf-3), leading to the activation of caspase-3 and apoptosis. This activation requires ATP. Isoform 6 is less effective in inducing apoptosis. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Caspase recruitment domains (CARDs) are members of the death domain superfamily and contain six antiparallel helices in an alpha-helical Greek key topology. We have examined the equilibrium and kinetic folding of the CARD of Apaf-1 (apoptotic protease activating factor 1), which consists of 97 amino acid residues, at pH 6 and pH 8. The results showed that an apparent two state equilibrium mechanism is not adequate to describe the folding of Apaf-1 CARD at either pH, suggesting the presence of intermediates in equilibrium unfolding. Interestingly, the results showed that the secondary structure is less stable than the tertiary structure, based on the transition mid-points for unfolding. Single mixing and sequential mixing stopped-flow studies showed that Apaf-1 CARD folds and unfolds rapidly and suggest a folding mechanism that contains parallel channels with two unfolded conformations folding to the native conformation. Kinetic simulations show that a slow folding phase is described by a third conformation in the unfolded ensemble that interconverts with one or both unfolded species. Overall, the native ensemble is formed rapidly upon refolding. This is in contrast to other CARDs in which folding appears to be dominated by formation of kinetic traps. Rapid folding and unfolding of Apaf-1 CARD.,Milam SL, Nicely NI, Feeney B, Mattos C, Clark AC J Mol Biol. 2007 May 25;369(1):290-304. Epub 2007 Mar 15. PMID:17408690 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Apoptotic protease-activating factor-1 3D structures

spinqualitylabelsall models 2p1h, resolution 1.59Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image