Structural insights into the mechanism of protein transport by the Type 9 Secretion System translocon
Secretion systems are protein export machines that enable bacteria to exploit their environment through the release of protein effectors. The Type 9 Secretion System (T9SS) is responsible for protein export across the outer membrane (OM) of bacteria of the phylum Bacteroidota. Here we trap the T9SS...
| Main Authors: | , , , , , , , |
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| Format: | Journal article |
| Language: | English |
| Published: |
Springer Nature
2024
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| _version_ | 1797113213409558528 |
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| author | Lauber, F Deme, JC Liu, X Kjær, A Miller, HL Alcock, F Lea, SM Berks, BC |
| author_facet | Lauber, F Deme, JC Liu, X Kjær, A Miller, HL Alcock, F Lea, SM Berks, BC |
| author_sort | Lauber, F |
| collection | OXFORD |
| description | Secretion systems are protein export machines that enable bacteria to exploit their environment through the release of protein effectors. The Type 9 Secretion System (T9SS) is responsible for protein export across the outer membrane (OM) of bacteria of the phylum Bacteroidota. Here we trap the T9SS of <i>Flavobacterium johnsoniae</i> in the process of substrate transport by disrupting the T9SS motor complex. Cryo-EM analysis of purified substrate-bound T9SS translocons reveals an extended translocon structure in which the previously described translocon core is augmented by a periplasmic structure incorporating the proteins SprE, PorD and a homologue of the canonical periplasmic chaperone Skp. Substrate proteins bind to the extracellular loops of a carrier protein within the translocon pore. As transport intermediates accumulate on the translocon when energetic input is removed, we deduce that release of the substrate–carrier protein complex from the translocon is the energy-requiring step in T9SS transport. |
| first_indexed | 2024-03-07T08:25:50Z |
| format | Journal article |
| id | oxford-uuid:30e84574-4b81-470c-a763-8a18151cb825 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-04-23T08:25:15Z |
| publishDate | 2024 |
| publisher | Springer Nature |
| record_format | dspace |
| spelling | oxford-uuid:30e84574-4b81-470c-a763-8a18151cb8252024-04-18T10:16:30ZStructural insights into the mechanism of protein transport by the Type 9 Secretion System transloconJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:30e84574-4b81-470c-a763-8a18151cb825EnglishSymplectic ElementsSpringer Nature2024Lauber, FDeme, JCLiu, XKjær, AMiller, HLAlcock, FLea, SMBerks, BCSecretion systems are protein export machines that enable bacteria to exploit their environment through the release of protein effectors. The Type 9 Secretion System (T9SS) is responsible for protein export across the outer membrane (OM) of bacteria of the phylum Bacteroidota. Here we trap the T9SS of <i>Flavobacterium johnsoniae</i> in the process of substrate transport by disrupting the T9SS motor complex. Cryo-EM analysis of purified substrate-bound T9SS translocons reveals an extended translocon structure in which the previously described translocon core is augmented by a periplasmic structure incorporating the proteins SprE, PorD and a homologue of the canonical periplasmic chaperone Skp. Substrate proteins bind to the extracellular loops of a carrier protein within the translocon pore. As transport intermediates accumulate on the translocon when energetic input is removed, we deduce that release of the substrate–carrier protein complex from the translocon is the energy-requiring step in T9SS transport. |
| spellingShingle | Lauber, F Deme, JC Liu, X Kjær, A Miller, HL Alcock, F Lea, SM Berks, BC Structural insights into the mechanism of protein transport by the Type 9 Secretion System translocon |
| title | Structural insights into the mechanism of protein transport by the Type 9 Secretion System translocon |
| title_full | Structural insights into the mechanism of protein transport by the Type 9 Secretion System translocon |
| title_fullStr | Structural insights into the mechanism of protein transport by the Type 9 Secretion System translocon |
| title_full_unstemmed | Structural insights into the mechanism of protein transport by the Type 9 Secretion System translocon |
| title_short | Structural insights into the mechanism of protein transport by the Type 9 Secretion System translocon |
| title_sort | structural insights into the mechanism of protein transport by the type 9 secretion system translocon |
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