The N-Terminal Membrane-Spanning Domain of the <named-content content-type="genus-species">Escherichia coli</named-content> DNA Translocase FtsK Hexamerizes at Midcell

ABSTRACT Bacterial FtsK plays a key role in coordinating cell division with the late stages of chromosome segregation. The N-terminal membrane-spanning domain of FtsK is required for cell division, whereas the C-terminal domain is a fast double-stranded DNA (dsDNA) translocase that brings the replic...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Paola Bisicchia, Bradley Steel, Mekdes H. Mariam Debela, Jan Löwe, David Sherratt
Formato:	article
Lenguaje:	EN
Publicado:	American Society for Microbiology 2013
Materias:	Microbiology QR1-502
Acceso en línea:	https://doaj.org/article/94238abc325449689a7cac768f194fa9
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:94238abc325449689a7cac768f194fa9
record_format	dspace
spelling	oai:doaj.org-article:94238abc325449689a7cac768f194fa92021-11-15T15:42:32ZThe N-Terminal Membrane-Spanning Domain of the <named-content content-type="genus-species">Escherichia coli</named-content> DNA Translocase FtsK Hexamerizes at Midcell10.1128/mBio.00800-132150-7511https://doaj.org/article/94238abc325449689a7cac768f194fa92013-12-01T00:00:00Zhttps://journals.asm.org/doi/10.1128/mBio.00800-13https://doaj.org/toc/2150-7511ABSTRACT Bacterial FtsK plays a key role in coordinating cell division with the late stages of chromosome segregation. The N-terminal membrane-spanning domain of FtsK is required for cell division, whereas the C-terminal domain is a fast double-stranded DNA (dsDNA) translocase that brings the replication termination region of the chromosome to midcell, where it facilitates chromosome unlinking by activating XerCD-dif site-specific recombination. Therefore, FtsK coordinates the late stages of chromosome segregation with cell division. Although the translocase is known to act as a hexamer on DNA, it is unknown when and how hexamers form, as is the number of FtsK molecules in the cell and within the divisome. Using single-molecule live-cell imaging, we show that newborn Escherichia coli cells growing in minimal medium contain ~40 membrane-bound FtsK molecules that are largely monomeric; the numbers increase proportionately with cell growth. After recruitment to the midcell, FtsK is present only as hexamers. Hexamers are observed in all cells and form before any visible sign of cell constriction. An average of 7 FtsK hexamers per cell are present at midcell, with the N-terminal domain being able to hexamerize independently of the translocase. Detergent-solubilized and purified FtsK N-terminal domains readily form hexamers, as determined by in vitro biochemistry, thereby supporting the in vivo data. The hexameric state of the FtsK N-terminal domain at the division site may facilitate assembly of a functional C-terminal DNA translocase on chromosomal DNA. IMPORTANCE In the rod-shaped bacterium Escherichia coli, more than a dozen proteins act at the cell center to mediate cell division, which initiates while chromosome replication and segregation are under way. The protein FtsK coordinates cell division with the late stages of chromosome segregation. The N-terminal part of FtsK is membrane embedded and acts in division, while the C-terminal part forms a hexameric ring on chromosomal DNA, which the DNA can translocate rapidly to finalize chromosome segregation. Using quantitative live-cell imaging, which measures the position and number of FtsK molecules, we show that in all cells, FtsK hexamers form only at the cell center at the initiation of cell division. Furthermore, the FtsK N-terminal portion forms hexamers independently of the C-terminal translocase.Paola BisicchiaBradley SteelMekdes H. Mariam DebelaJan LöweDavid SherrattAmerican Society for MicrobiologyarticleMicrobiologyQR1-502ENmBio, Vol 4, Iss 6 (2013)
institution	DOAJ
collection	DOAJ
language	EN
topic	Microbiology QR1-502
spellingShingle	Microbiology QR1-502 Paola Bisicchia Bradley Steel Mekdes H. Mariam Debela Jan Löwe David Sherratt The N-Terminal Membrane-Spanning Domain of the <named-content content-type="genus-species">Escherichia coli</named-content> DNA Translocase FtsK Hexamerizes at Midcell
description	ABSTRACT Bacterial FtsK plays a key role in coordinating cell division with the late stages of chromosome segregation. The N-terminal membrane-spanning domain of FtsK is required for cell division, whereas the C-terminal domain is a fast double-stranded DNA (dsDNA) translocase that brings the replication termination region of the chromosome to midcell, where it facilitates chromosome unlinking by activating XerCD-dif site-specific recombination. Therefore, FtsK coordinates the late stages of chromosome segregation with cell division. Although the translocase is known to act as a hexamer on DNA, it is unknown when and how hexamers form, as is the number of FtsK molecules in the cell and within the divisome. Using single-molecule live-cell imaging, we show that newborn Escherichia coli cells growing in minimal medium contain ~40 membrane-bound FtsK molecules that are largely monomeric; the numbers increase proportionately with cell growth. After recruitment to the midcell, FtsK is present only as hexamers. Hexamers are observed in all cells and form before any visible sign of cell constriction. An average of 7 FtsK hexamers per cell are present at midcell, with the N-terminal domain being able to hexamerize independently of the translocase. Detergent-solubilized and purified FtsK N-terminal domains readily form hexamers, as determined by in vitro biochemistry, thereby supporting the in vivo data. The hexameric state of the FtsK N-terminal domain at the division site may facilitate assembly of a functional C-terminal DNA translocase on chromosomal DNA. IMPORTANCE In the rod-shaped bacterium Escherichia coli, more than a dozen proteins act at the cell center to mediate cell division, which initiates while chromosome replication and segregation are under way. The protein FtsK coordinates cell division with the late stages of chromosome segregation. The N-terminal part of FtsK is membrane embedded and acts in division, while the C-terminal part forms a hexameric ring on chromosomal DNA, which the DNA can translocate rapidly to finalize chromosome segregation. Using quantitative live-cell imaging, which measures the position and number of FtsK molecules, we show that in all cells, FtsK hexamers form only at the cell center at the initiation of cell division. Furthermore, the FtsK N-terminal portion forms hexamers independently of the C-terminal translocase.
format	article
author	Paola Bisicchia Bradley Steel Mekdes H. Mariam Debela Jan Löwe David Sherratt
author_facet	Paola Bisicchia Bradley Steel Mekdes H. Mariam Debela Jan Löwe David Sherratt
author_sort	Paola Bisicchia
title	The N-Terminal Membrane-Spanning Domain of the <named-content content-type="genus-species">Escherichia coli</named-content> DNA Translocase FtsK Hexamerizes at Midcell
title_short	The N-Terminal Membrane-Spanning Domain of the <named-content content-type="genus-species">Escherichia coli</named-content> DNA Translocase FtsK Hexamerizes at Midcell
title_full	The N-Terminal Membrane-Spanning Domain of the <named-content content-type="genus-species">Escherichia coli</named-content> DNA Translocase FtsK Hexamerizes at Midcell
title_fullStr	The N-Terminal Membrane-Spanning Domain of the <named-content content-type="genus-species">Escherichia coli</named-content> DNA Translocase FtsK Hexamerizes at Midcell
title_full_unstemmed	The N-Terminal Membrane-Spanning Domain of the <named-content content-type="genus-species">Escherichia coli</named-content> DNA Translocase FtsK Hexamerizes at Midcell
title_sort	n-terminal membrane-spanning domain of the <named-content content-type="genus-species">escherichia coli</named-content> dna translocase ftsk hexamerizes at midcell
publisher	American Society for Microbiology
publishDate	2013
url	https://doaj.org/article/94238abc325449689a7cac768f194fa9
work_keys_str_mv	AT paolabisicchia thenterminalmembranespanningdomainofthenamedcontentcontenttypegenusspeciesescherichiacolinamedcontentdnatranslocaseftskhexamerizesatmidcell AT bradleysteel thenterminalmembranespanningdomainofthenamedcontentcontenttypegenusspeciesescherichiacolinamedcontentdnatranslocaseftskhexamerizesatmidcell AT mekdeshmariamdebela thenterminalmembranespanningdomainofthenamedcontentcontenttypegenusspeciesescherichiacolinamedcontentdnatranslocaseftskhexamerizesatmidcell AT janlowe thenterminalmembranespanningdomainofthenamedcontentcontenttypegenusspeciesescherichiacolinamedcontentdnatranslocaseftskhexamerizesatmidcell AT davidsherratt thenterminalmembranespanningdomainofthenamedcontentcontenttypegenusspeciesescherichiacolinamedcontentdnatranslocaseftskhexamerizesatmidcell AT paolabisicchia nterminalmembranespanningdomainofthenamedcontentcontenttypegenusspeciesescherichiacolinamedcontentdnatranslocaseftskhexamerizesatmidcell AT bradleysteel nterminalmembranespanningdomainofthenamedcontentcontenttypegenusspeciesescherichiacolinamedcontentdnatranslocaseftskhexamerizesatmidcell AT mekdeshmariamdebela nterminalmembranespanningdomainofthenamedcontentcontenttypegenusspeciesescherichiacolinamedcontentdnatranslocaseftskhexamerizesatmidcell AT janlowe nterminalmembranespanningdomainofthenamedcontentcontenttypegenusspeciesescherichiacolinamedcontentdnatranslocaseftskhexamerizesatmidcell AT davidsherratt nterminalmembranespanningdomainofthenamedcontentcontenttypegenusspeciesescherichiacolinamedcontentdnatranslocaseftskhexamerizesatmidcell
_version_	1718427599949004800

The N-Terminal Membrane-Spanning Domain of the <named-content content-type="genus-species">Escherichia coli</named-content> DNA Translocase FtsK Hexamerizes at Midcell

Ejemplares similares