6rgi
From Proteopedia
Partially unfolded cytochrome c in complex with sulfonatocalix[6]arene
Structural highlights
FunctionCYC1_YEAST Electron carrier protein. The oxidized form of the cytochrome c heme group can accept an electron from the heme group of the cytochrome c1 subunit of cytochrome reductase. Cytochrome c then transfers this electron to the cytochrome oxidase complex, the final protein carrier in the mitochondrial electron-transport chain. Publication Abstract from PubMedSupramolecular receptors such as water-soluble calixarenes are in development as 'molecular glues' for protein assembly. Here, we obtained cocrystals of sulfonato-calix[6]arene (sclx6 ) and yeast cytochrome c (cytc) in the presence of imidazole. A crystal structure at 2.65 A resolution reveals major structural rearrangement and disorder in imidazole-bound cytc. The largest protein-calixarene interface involves 440 A(2) of the protein surface with key contacts at Arg13, Lys73, and Lys79. These lysines participate in alkaline transitions of cytc and are part of Omega-loop D, which is substantially restructured in the complex with sclx6 . The structural modification also includes Omega-loop C, which is disordered (residues 41-55 inclusive). These results suggest the possibility of using supramolecular scaffolds to trap partially disordered proteins. Calixarene capture of partially unfolded cytochrome c.,Engilberge S, Rennie ML, Crowley PB FEBS Lett. 2019 Jun 29. doi: 10.1002/1873-3468.13512. PMID:31254353[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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