3MI0
Crystal Structure of Mycobacterium Tuberculosis Proteasome at 2.2 A
Summary for 3MI0
| Entry DOI | 10.2210/pdb3mi0/pdb |
| Descriptor | Proteasome subunit alpha, Proteasome subunit beta, DIMETHYLFORMAMIDE, ... (5 entities in total) |
| Functional Keywords | enzyme inhibitors, lactones, proteasome endopeptidase complex, mycobacterium tuberculosis, hydrolase |
| Biological source | Mycobacterium tuberculosis More |
| Cellular location | Cytoplasm (By similarity): O33244 O33245 |
| Total number of polymer chains | 28 |
| Total formula weight | 743523.66 |
| Authors | |
| Primary citation | Li, D.,Li, H.,Wang, T.,Pan, H.,Lin, G.,Li, H. Structural basis for the assembly and gate closure mechanisms of the Mycobacterium tuberculosis 20S proteasome. Embo J., 2010 Cited by PubMed Abstract: Mycobacterium tuberculosis (Mtb) possesses a proteasome system analogous to the eukaryotic ubiquitin-proteasome pathway. Mtb requires the proteasome to resist killing by the host immune system. The detailed assembly process and the gating mechanism of Mtb proteasome have remained unknown. Using cryo-electron microscopy and X-ray crystallography, we have obtained structures of three Mtb proteasome assembly intermediates, showing conformational changes during assembly, and explaining why the beta-subunit propeptide inhibits rather than promotes assembly. Although the eukaryotic proteasome core particles close their protein substrate entrance gates with different amino terminal peptides of the seven alpha-subunits, it has been unknown how a prokaryotic proteasome might close the gate at the symmetry axis with seven identical peptides. We found in the new Mtb proteasome crystal structure that the gate is tightly sealed by the seven identical peptides taking on three distinct conformations. Our work provides the structural bases for assembly and gating mechanisms of the Mtb proteasome. PubMed: 20461058DOI: 10.1038/emboj.2010.95 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.2 Å) |
Structure validation
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