4BWG
Structural basis of subtilase cytotoxin SubAB assembly
Summary for 4BWG
| Entry DOI | 10.2210/pdb4bwg/pdb |
| Descriptor | SUBA, SUBTILASE CYTOTOXIN, SUBUNIT B, GLYCEROL, ... (5 entities in total) |
| Functional Keywords | toxin, ab5 toxins, disassembly, cellular trafficking |
| Biological source | ESCHERICHIA COLI More |
| Total number of polymer chains | 12 |
| Total formula weight | 207307.12 |
| Authors | Le Nours, J.,Paton, A.W.,Byres, E.,Troy, S.,Herdman, B.P.,Johnson, M.D.,Paton, J.C.,Rossjohn, J.,Beddoe, T. (deposition date: 2013-07-02, release date: 2013-08-14, Last modification date: 2024-10-23) |
| Primary citation | Le Nours, J.,Paton, A.W.,Byres, E.,Troy, S.,Herdman, B.P.,Johnson, M.D.,Paton, J.C.,Rossjohn, J.,Beddoe, T. Structural Basis of Subtilase Cytotoxin Subab Assembly. J.Biol.Chem., 288:27505-, 2013 Cited by PubMed Abstract: Pathogenic strains of Escherichia coli produce a number of toxins that belong to the AB5 toxin family, which comprise a catalytic A-subunit that induces cellular dysfunction and a B-pentamer that recognizes host glycans. Although the molecular actions of many of the individual subunits of AB5 toxins are well understood, how they self-associate and the effect of this association on cytotoxicity are poorly understood. Here we have solved the structure of the holo-SubAB toxin that, in contrast to other AB5 toxins whose molecular targets are located in the cytosol, cleaves the endoplasmic reticulum chaperone BiP. SubA interacts with SubB in a similar manner to other AB5 toxins via the A2 helix and a conserved disulfide bond that joins the A1 domain with the A2 helix. The structure revealed that the active site of SubA is not occluded by the B-pentamer, and the B-pentamer does not enhance or inhibit the activity of SubA. Structure-based sequence comparisons with other AB5 toxin family members, combined with extensive mutagenesis studies on SubB, show how the hydrophobic patch on top of the B-pentamer plays a dominant role in binding the A-subunit. The structure of SubAB and the accompanying functional characterization of various mutants of SubAB provide a framework for understanding the important role of the B-pentamer in the assembly and the intracellular trafficking of this AB5 toxin. PubMed: 23921389DOI: 10.1074/JBC.M113.462622 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.6 Å) |
Structure validation
Download full validation report
