6S3L
Structure of the core of the flagellar export apparatus from Vibrio mimicus, the FliPQR-FlhB complex.
Summary for 6S3L
| Entry DOI | 10.2210/pdb6s3l/pdb |
| EMDB information | 10093 |
| Descriptor | Flagellar biosynthetic protein FliP, Flagellar biosynthetic protein FliR, Flagellar biosynthetic protein FliQ, ... (4 entities in total) |
| Functional Keywords | flagella, t3ss, export apparatus, export gate, protein transport |
| Biological source | Vibrio mimicus CAIM 602 More |
| Total number of polymer chains | 11 |
| Total formula weight | 278520.90 |
| Authors | Kuhlen, L.,Johnson, S.,Deme, J.C.,Lea, S.M. (deposition date: 2019-06-25, release date: 2020-03-25, Last modification date: 2024-05-22) |
| Primary citation | Kuhlen, L.,Johnson, S.,Zeitler, A.,Baurle, S.,Deme, J.C.,Caesar, J.J.E.,Debo, R.,Fisher, J.,Wagner, S.,Lea, S.M. The substrate specificity switch FlhB assembles onto the export gate to regulate type three secretion. Nat Commun, 11:1296-1296, 2020 Cited by PubMed Abstract: Protein secretion through type-three secretion systems (T3SS) is critical for motility and virulence of many bacteria. Proteins are transported through an export gate containing three proteins (FliPQR in flagella, SctRST in virulence systems). A fourth essential T3SS protein (FlhB/SctU) functions to "switch" secretion substrate specificity once the growing hook/needle reach their determined length. Here, we present the cryo-electron microscopy structure of an export gate containing the switch protein from a Vibrio flagellar system at 3.2 Å resolution. The structure reveals that FlhB/SctU extends the helical export gate with its four predicted transmembrane helices wrapped around FliPQR/SctRST. The unusual topology of the FlhB/SctU helices creates a loop wrapped around the bottom of the closed export gate. Structure-informed mutagenesis suggests that this loop is critical in gating secretion and we propose that a series of conformational changes in the T3SS trigger opening of the gate through interactions between FlhB/SctU and FliPQR/SctRST. PubMed: 32157081DOI: 10.1038/s41467-020-15071-9 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (3.2 Å) |
Structure validation
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