4MCT
P. vulgaris HIGBA structure, crystal form 1
Summary for 4MCT
| Entry DOI | 10.2210/pdb4mct/pdb |
| Related | 4MCX |
| Descriptor | Antidote protein, Killer protein (3 entities in total) |
| Functional Keywords | bacterial toxins, biofilms, cell metabolism, energy metabolism, helix-turn-helix transcription factors, microbial pathogenesis, stress response, stringent response, transcription repressor, translation control, toxin |
| Biological source | Proteus vulgaris More |
| Total number of polymer chains | 4 |
| Total formula weight | 50004.62 |
| Authors | Schureck, M.A.,Maehigashi, T.,Dunham, C.M. (deposition date: 2013-08-21, release date: 2013-12-11, Last modification date: 2024-10-09) |
| Primary citation | Schureck, M.A.,Maehigashi, T.,Miles, S.J.,Marquez, J.,Cho, S.E.,Erdman, R.,Dunham, C.M. Structure of the Proteus vulgaris HigB-(HigA)2-HigB Toxin-Antitoxin Complex. J.Biol.Chem., 289:1060-1070, 2014 Cited by PubMed Abstract: Bacterial toxin-antitoxin (TA) systems regulate key cellular processes to promote cell survival during periods of stress. During steady-state cell growth, antitoxins typically interact with their cognate toxins to inhibit activity presumably by preventing substrate recognition. We solved two x-ray crystal structures of the Proteus vulgaris tetrameric HigB-(HigA)2-HigB TA complex and found that, unlike most other TA systems, the antitoxin HigA makes minimal interactions with toxin HigB. HigB adopts a RelE family tertiary fold containing a highly conserved concave surface where we predict its active site is located. HigA does not cover the solvent-exposed HigB active site, suggesting that, in general, toxin inhibition is not solely mediated by active site hindrance by its antitoxin. Each HigA monomer contains a helix-turn-helix motif that binds to its own DNA operator to repress transcription during normal cellular growth. This is distinct from antitoxins belonging to other superfamilies that typically only form DNA-binding motifs upon dimerization. We further show that disruption of the HigB-(HigA)2-HigB tetramer to a HigBA heterodimer ablates operator binding. Taken together, our biochemical and structural studies elucidate the novel molecular details of the HigBA TA system. PubMed: 24257752DOI: 10.1074/jbc.M113.512095 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.8 Å) |
Structure validation
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