New insights into the Tat protein transport cycle from characterising the assembled Tat translocon
The twin-arginine protein translocation (Tat) system transports folded proteins across the bacterial cytoplasmic membrane and the thylakoid membrane of chloroplasts. The Tat translocation site is transiently assembled by the recruitment of multiple TatA proteins to a substrate-activated TatBC recept...
| Glavni autori: | , |
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| Format: | Journal article |
| Jezik: | English |
| Izdano: |
Wiley
2022
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| _version_ | 1826309375838388224 |
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| author | Alcock, F Berks, BC |
| author_facet | Alcock, F Berks, BC |
| author_sort | Alcock, F |
| collection | OXFORD |
| description | The twin-arginine protein translocation (Tat) system transports folded proteins across the bacterial cytoplasmic membrane and the thylakoid membrane of chloroplasts. The Tat translocation site is transiently assembled by the recruitment of multiple TatA proteins to a substrate-activated TatBC receptor complex in a process requiring the protonmotive force. The ephemeral nature of the Tat translocation site has so far precluded its isolation. We now report that detergent solubilization of membranes during active transport allows the recovery of receptor complexes that are associated with elevated levels of TatA. We apply this biochemical analysis in combination with live cell fluorescence imaging to Tat systems trapped in the assembled state. We resolve sub-steps in the Tat translocation cycle and infer that TatA assembly precedes the functional interaction of TatA with a polar cluster site on TatC. We observe that dissipation of the protonmotive force releases TatA oligomers from the assembled translocation site demonstrating that the stability of the TatA oligomer does not depend on binding to the receptor complex and implying that the TatA oligomer is assembled at the periphery of the receptor complex. This work provides new insight into the Tat transport cycle and advances efforts to isolate the active Tat translocon. |
| first_indexed | 2024-03-07T07:34:46Z |
| format | Journal article |
| id | oxford-uuid:56d6ba73-8314-4fd6-b460-7d294ebd2a78 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T07:34:46Z |
| publishDate | 2022 |
| publisher | Wiley |
| record_format | dspace |
| spelling | oxford-uuid:56d6ba73-8314-4fd6-b460-7d294ebd2a782023-02-24T08:13:47ZNew insights into the Tat protein transport cycle from characterising the assembled Tat transloconJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:56d6ba73-8314-4fd6-b460-7d294ebd2a78EnglishSymplectic ElementsWiley2022Alcock, FBerks, BCThe twin-arginine protein translocation (Tat) system transports folded proteins across the bacterial cytoplasmic membrane and the thylakoid membrane of chloroplasts. The Tat translocation site is transiently assembled by the recruitment of multiple TatA proteins to a substrate-activated TatBC receptor complex in a process requiring the protonmotive force. The ephemeral nature of the Tat translocation site has so far precluded its isolation. We now report that detergent solubilization of membranes during active transport allows the recovery of receptor complexes that are associated with elevated levels of TatA. We apply this biochemical analysis in combination with live cell fluorescence imaging to Tat systems trapped in the assembled state. We resolve sub-steps in the Tat translocation cycle and infer that TatA assembly precedes the functional interaction of TatA with a polar cluster site on TatC. We observe that dissipation of the protonmotive force releases TatA oligomers from the assembled translocation site demonstrating that the stability of the TatA oligomer does not depend on binding to the receptor complex and implying that the TatA oligomer is assembled at the periphery of the receptor complex. This work provides new insight into the Tat transport cycle and advances efforts to isolate the active Tat translocon. |
| spellingShingle | Alcock, F Berks, BC New insights into the Tat protein transport cycle from characterising the assembled Tat translocon |
| title | New insights into the Tat protein transport cycle from characterising the assembled Tat translocon |
| title_full | New insights into the Tat protein transport cycle from characterising the assembled Tat translocon |
| title_fullStr | New insights into the Tat protein transport cycle from characterising the assembled Tat translocon |
| title_full_unstemmed | New insights into the Tat protein transport cycle from characterising the assembled Tat translocon |
| title_short | New insights into the Tat protein transport cycle from characterising the assembled Tat translocon |
| title_sort | new insights into the tat protein transport cycle from characterising the assembled tat translocon |
| work_keys_str_mv | AT alcockf newinsightsintothetatproteintransportcyclefromcharacterisingtheassembledtattranslocon AT berksbc newinsightsintothetatproteintransportcyclefromcharacterisingtheassembledtattranslocon |