4XC7
Isobutyryl-CoA mutase fused with bound butyryl-CoA and without cobalamin or GDP (apo-IcmF)
Summary for 4XC7
| Entry DOI | 10.2210/pdb4xc7/pdb |
| Related | 4XC6 4XC8 |
| Descriptor | Isobutyryl-CoA mutase fused, Butyryl Coenzyme A, L(+)-TARTARIC ACID (3 entities in total) |
| Functional Keywords | radical enzyme, complex, isomerase, g-protein chaperone |
| Biological source | Ralstonia metallidurans (strain CH34 / ATCC 43123 / DSM 2839) |
| Total number of polymer chains | 2 |
| Total formula weight | 247830.59 |
| Authors | Jost, M.,Drennan, C.L. (deposition date: 2014-12-17, release date: 2015-02-11, Last modification date: 2023-09-27) |
| Primary citation | Jost, M.,Cracan, V.,Hubbard, P.A.,Banerjee, R.,Drennan, C.L. Visualization of a radical B12 enzyme with its G-protein chaperone. Proc.Natl.Acad.Sci.USA, 112:2419-2424, 2015 Cited by PubMed Abstract: G-protein metallochaperones ensure fidelity during cofactor assembly for a variety of metalloproteins, including adenosylcobalamin (AdoCbl)-dependent methylmalonyl-CoA mutase and hydrogenase, and thus have both medical and biofuel development applications. Here, we present crystal structures of IcmF, a natural fusion protein of AdoCbl-dependent isobutyryl-CoA mutase and its corresponding G-protein chaperone, which reveal the molecular architecture of a G-protein metallochaperone in complex with its target protein. These structures show that conserved G-protein elements become ordered upon target protein association, creating the molecular pathways that both sense and report on the cofactor loading state. Structures determined of both apo- and holo-forms of IcmF depict both open and closed enzyme states, in which the cofactor-binding domain is alternatively positioned for cofactor loading and for catalysis. Notably, the G protein moves as a unit with the cofactor-binding domain, providing a visualization of how a chaperone assists in the sequestering of a precious cofactor inside an enzyme active site. PubMed: 25675500DOI: 10.1073/pnas.1419582112 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (3.45 Å) |
Structure validation
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