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Type VI secretion system: secretion by a contractile nanomachine

The type VI secretion systems (T6SS) are present in about a quarter of all Gram-negative bacteria. Several key components of T6SS are evolutionarily related to components of contractile nanomachines such as phages and R-type pyocins. The T6SS assembly is initiated by formation of a membrane complex...

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Detalles Bibliográficos
Autor principal: Basler, Marek
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4632598/
https://www.ncbi.nlm.nih.gov/pubmed/26370934
http://dx.doi.org/10.1098/rstb.2015.0021
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author Basler, Marek
author_facet Basler, Marek
author_sort Basler, Marek
collection PubMed
description The type VI secretion systems (T6SS) are present in about a quarter of all Gram-negative bacteria. Several key components of T6SS are evolutionarily related to components of contractile nanomachines such as phages and R-type pyocins. The T6SS assembly is initiated by formation of a membrane complex that binds a phage-like baseplate with a sharp spike, and this is followed by polymerization of a long rigid inner tube and an outer contractile sheath. Effectors are preloaded onto the spike or into the tube during the assembly by various mechanisms. Contraction of the sheath releases an unprecedented amount of energy, which is used to thrust the spike and tube with the associated effectors out of the effector cell and across membranes of both bacterial and eukaryotic target cells. Subunits of the contracted sheath are recycled by T6SS-specific unfoldase to allow for a new round of assembly. Live-cell imaging has shown that the assembly is highly dynamic and its subcellular localization is in certain bacteria regulated with a remarkable precision. Through the action of effectors, T6SS has mainly been shown to contribute to pathogenicity and competition between bacteria. This review summarizes the knowledge that has contributed to our current understanding of T6SS mode of action.
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spelling pubmed-46325982015-11-05 Type VI secretion system: secretion by a contractile nanomachine Basler, Marek Philos Trans R Soc Lond B Biol Sci Articles The type VI secretion systems (T6SS) are present in about a quarter of all Gram-negative bacteria. Several key components of T6SS are evolutionarily related to components of contractile nanomachines such as phages and R-type pyocins. The T6SS assembly is initiated by formation of a membrane complex that binds a phage-like baseplate with a sharp spike, and this is followed by polymerization of a long rigid inner tube and an outer contractile sheath. Effectors are preloaded onto the spike or into the tube during the assembly by various mechanisms. Contraction of the sheath releases an unprecedented amount of energy, which is used to thrust the spike and tube with the associated effectors out of the effector cell and across membranes of both bacterial and eukaryotic target cells. Subunits of the contracted sheath are recycled by T6SS-specific unfoldase to allow for a new round of assembly. Live-cell imaging has shown that the assembly is highly dynamic and its subcellular localization is in certain bacteria regulated with a remarkable precision. Through the action of effectors, T6SS has mainly been shown to contribute to pathogenicity and competition between bacteria. This review summarizes the knowledge that has contributed to our current understanding of T6SS mode of action. The Royal Society 2015-10-05 /pmc/articles/PMC4632598/ /pubmed/26370934 http://dx.doi.org/10.1098/rstb.2015.0021 Text en © 2015 The Authors. http://creativecommons.org/licenses/by/4.0/ Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited.
spellingShingle Articles
Basler, Marek
Type VI secretion system: secretion by a contractile nanomachine
title Type VI secretion system: secretion by a contractile nanomachine
title_full Type VI secretion system: secretion by a contractile nanomachine
title_fullStr Type VI secretion system: secretion by a contractile nanomachine
title_full_unstemmed Type VI secretion system: secretion by a contractile nanomachine
title_short Type VI secretion system: secretion by a contractile nanomachine
title_sort type vi secretion system: secretion by a contractile nanomachine
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4632598/
https://www.ncbi.nlm.nih.gov/pubmed/26370934
http://dx.doi.org/10.1098/rstb.2015.0021
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