Forward Genetic Dissection of Biofilm Development by <named-content content-type="genus-species">Fusobacterium nucleatum</named-content>: Novel Functions of Cell Division Proteins FtsX and EnvC

ABSTRACT Fusobacterium nucleatum is a key member of the human oral biofilm. It is also implicated in preterm birth and colorectal cancer. To facilitate basic studies of fusobacterial virulence, we describe here a versatile transposon mutagenesis procedure and a pilot screen for mutants defective in...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Chenggang Wu, Abu Amar Mohamed Al Mamun, Truc Thanh Luong, Bo Hu, Jianhua Gu, Ju Huck Lee, Melissa D’Amore, Asis Das, Hung Ton-That
Formato: article
Lenguaje:EN
Publicado: American Society for Microbiology 2018
Materias:
Acceso en línea:https://doaj.org/article/199fbf53faad457d9eba849871f7d978
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
id oai:doaj.org-article:199fbf53faad457d9eba849871f7d978
record_format dspace
spelling oai:doaj.org-article:199fbf53faad457d9eba849871f7d9782021-11-15T15:53:27ZForward Genetic Dissection of Biofilm Development by <named-content content-type="genus-species">Fusobacterium nucleatum</named-content>: Novel Functions of Cell Division Proteins FtsX and EnvC10.1128/mBio.00360-182150-7511https://doaj.org/article/199fbf53faad457d9eba849871f7d9782018-05-01T00:00:00Zhttps://journals.asm.org/doi/10.1128/mBio.00360-18https://doaj.org/toc/2150-7511ABSTRACT Fusobacterium nucleatum is a key member of the human oral biofilm. It is also implicated in preterm birth and colorectal cancer. To facilitate basic studies of fusobacterial virulence, we describe here a versatile transposon mutagenesis procedure and a pilot screen for mutants defective in biofilm formation. Out of 10 independent biofilm-defective mutants isolated, the affected genes included the homologs of the Escherichia coli cell division proteins FtsX and EnvC, the electron transport protein RnfA, and four proteins with unknown functions. Next, a facile new gene deletion method demonstrated that nonpolar, in-frame deletion of ftsX or envC produces viable bacteria that are highly filamentous due to defective cell division. Transmission electron and cryo-electron microscopy revealed that the ΔftsX and ΔenvC mutant cells remain joined with apparent constriction, and scanning electron microscopy (EM) uncovered a smooth cell surface without the microfolds present in wild-type cells. FtsX and EnvC proteins interact with each other as well as a common set of interacting partners, many with unknown function. Last, biofilm development is altered when cell division is blocked by MinC overproduction; however, unlike the phenotypes of ΔftsX and ΔenvC mutants, a weakly adherent biofilm is formed, and the wild-type rugged cell surface is maintained. Therefore, FtsX and EnvC may perform novel functions in Fusobacterium cell biology. This is the first report of an unbiased approach to uncover genetic determinants of fusobacterial biofilm development. It points to an intriguing link among cytokinesis, cell surface dynamics, and biofilm formation, whose molecular underpinnings remain to be elucidated. IMPORTANCE Little is known about the virulence mechanisms and associated factors in F. nucleatum, due mainly to the lack of convenient genetic tools for this organism. We employed two efficient genetic strategies to identify F. nucleatum biofilm-defective mutants, revealing FtsX and EnvC among seven biofilm-associated factors. Electron microscopy established cell division defects of the ΔftsX and ΔenvC mutants, accompanied with a smooth cell surface, unlike the microfold, rugged appearance of wild-type bacteria. Proteomic studies demonstrated that FtsX and EnvC interact with each other as well as a set of common and unique interacting proteins, many with unknown functions. Importantly, blocking cell division by MinC overproduction led to formation of a weakly adherent biofilm, without alteration of the wild-type cell surface. Thus, this work links cell division and surface dynamics to biofilm development and lays a foundation for future genetic and biochemical investigations of basic cellular processes in this clinically significant pathogen.Chenggang WuAbu Amar Mohamed Al MamunTruc Thanh LuongBo HuJianhua GuJu Huck LeeMelissa D’AmoreAsis DasHung Ton-ThatAmerican Society for MicrobiologyarticleEnvCFtsXFusobacterium nucleatumallelic exchangebiofilmscell divisionMicrobiologyQR1-502ENmBio, Vol 9, Iss 2 (2018)
institution DOAJ
collection DOAJ
language EN
topic EnvC
FtsX
Fusobacterium nucleatum
allelic exchange
biofilms
cell division
Microbiology
QR1-502
spellingShingle EnvC
FtsX
Fusobacterium nucleatum
allelic exchange
biofilms
cell division
Microbiology
QR1-502
Chenggang Wu
Abu Amar Mohamed Al Mamun
Truc Thanh Luong
Bo Hu
Jianhua Gu
Ju Huck Lee
Melissa D’Amore
Asis Das
Hung Ton-That
Forward Genetic Dissection of Biofilm Development by <named-content content-type="genus-species">Fusobacterium nucleatum</named-content>: Novel Functions of Cell Division Proteins FtsX and EnvC
description ABSTRACT Fusobacterium nucleatum is a key member of the human oral biofilm. It is also implicated in preterm birth and colorectal cancer. To facilitate basic studies of fusobacterial virulence, we describe here a versatile transposon mutagenesis procedure and a pilot screen for mutants defective in biofilm formation. Out of 10 independent biofilm-defective mutants isolated, the affected genes included the homologs of the Escherichia coli cell division proteins FtsX and EnvC, the electron transport protein RnfA, and four proteins with unknown functions. Next, a facile new gene deletion method demonstrated that nonpolar, in-frame deletion of ftsX or envC produces viable bacteria that are highly filamentous due to defective cell division. Transmission electron and cryo-electron microscopy revealed that the ΔftsX and ΔenvC mutant cells remain joined with apparent constriction, and scanning electron microscopy (EM) uncovered a smooth cell surface without the microfolds present in wild-type cells. FtsX and EnvC proteins interact with each other as well as a common set of interacting partners, many with unknown function. Last, biofilm development is altered when cell division is blocked by MinC overproduction; however, unlike the phenotypes of ΔftsX and ΔenvC mutants, a weakly adherent biofilm is formed, and the wild-type rugged cell surface is maintained. Therefore, FtsX and EnvC may perform novel functions in Fusobacterium cell biology. This is the first report of an unbiased approach to uncover genetic determinants of fusobacterial biofilm development. It points to an intriguing link among cytokinesis, cell surface dynamics, and biofilm formation, whose molecular underpinnings remain to be elucidated. IMPORTANCE Little is known about the virulence mechanisms and associated factors in F. nucleatum, due mainly to the lack of convenient genetic tools for this organism. We employed two efficient genetic strategies to identify F. nucleatum biofilm-defective mutants, revealing FtsX and EnvC among seven biofilm-associated factors. Electron microscopy established cell division defects of the ΔftsX and ΔenvC mutants, accompanied with a smooth cell surface, unlike the microfold, rugged appearance of wild-type bacteria. Proteomic studies demonstrated that FtsX and EnvC interact with each other as well as a set of common and unique interacting proteins, many with unknown functions. Importantly, blocking cell division by MinC overproduction led to formation of a weakly adherent biofilm, without alteration of the wild-type cell surface. Thus, this work links cell division and surface dynamics to biofilm development and lays a foundation for future genetic and biochemical investigations of basic cellular processes in this clinically significant pathogen.
format article
author Chenggang Wu
Abu Amar Mohamed Al Mamun
Truc Thanh Luong
Bo Hu
Jianhua Gu
Ju Huck Lee
Melissa D’Amore
Asis Das
Hung Ton-That
author_facet Chenggang Wu
Abu Amar Mohamed Al Mamun
Truc Thanh Luong
Bo Hu
Jianhua Gu
Ju Huck Lee
Melissa D’Amore
Asis Das
Hung Ton-That
author_sort Chenggang Wu
title Forward Genetic Dissection of Biofilm Development by <named-content content-type="genus-species">Fusobacterium nucleatum</named-content>: Novel Functions of Cell Division Proteins FtsX and EnvC
title_short Forward Genetic Dissection of Biofilm Development by <named-content content-type="genus-species">Fusobacterium nucleatum</named-content>: Novel Functions of Cell Division Proteins FtsX and EnvC
title_full Forward Genetic Dissection of Biofilm Development by <named-content content-type="genus-species">Fusobacterium nucleatum</named-content>: Novel Functions of Cell Division Proteins FtsX and EnvC
title_fullStr Forward Genetic Dissection of Biofilm Development by <named-content content-type="genus-species">Fusobacterium nucleatum</named-content>: Novel Functions of Cell Division Proteins FtsX and EnvC
title_full_unstemmed Forward Genetic Dissection of Biofilm Development by <named-content content-type="genus-species">Fusobacterium nucleatum</named-content>: Novel Functions of Cell Division Proteins FtsX and EnvC
title_sort forward genetic dissection of biofilm development by <named-content content-type="genus-species">fusobacterium nucleatum</named-content>: novel functions of cell division proteins ftsx and envc
publisher American Society for Microbiology
publishDate 2018
url https://doaj.org/article/199fbf53faad457d9eba849871f7d978
work_keys_str_mv AT chenggangwu forwardgeneticdissectionofbiofilmdevelopmentbynamedcontentcontenttypegenusspeciesfusobacteriumnucleatumnamedcontentnovelfunctionsofcelldivisionproteinsftsxandenvc
AT abuamarmohamedalmamun forwardgeneticdissectionofbiofilmdevelopmentbynamedcontentcontenttypegenusspeciesfusobacteriumnucleatumnamedcontentnovelfunctionsofcelldivisionproteinsftsxandenvc
AT tructhanhluong forwardgeneticdissectionofbiofilmdevelopmentbynamedcontentcontenttypegenusspeciesfusobacteriumnucleatumnamedcontentnovelfunctionsofcelldivisionproteinsftsxandenvc
AT bohu forwardgeneticdissectionofbiofilmdevelopmentbynamedcontentcontenttypegenusspeciesfusobacteriumnucleatumnamedcontentnovelfunctionsofcelldivisionproteinsftsxandenvc
AT jianhuagu forwardgeneticdissectionofbiofilmdevelopmentbynamedcontentcontenttypegenusspeciesfusobacteriumnucleatumnamedcontentnovelfunctionsofcelldivisionproteinsftsxandenvc
AT juhucklee forwardgeneticdissectionofbiofilmdevelopmentbynamedcontentcontenttypegenusspeciesfusobacteriumnucleatumnamedcontentnovelfunctionsofcelldivisionproteinsftsxandenvc
AT melissadamore forwardgeneticdissectionofbiofilmdevelopmentbynamedcontentcontenttypegenusspeciesfusobacteriumnucleatumnamedcontentnovelfunctionsofcelldivisionproteinsftsxandenvc
AT asisdas forwardgeneticdissectionofbiofilmdevelopmentbynamedcontentcontenttypegenusspeciesfusobacteriumnucleatumnamedcontentnovelfunctionsofcelldivisionproteinsftsxandenvc
AT hungtonthat forwardgeneticdissectionofbiofilmdevelopmentbynamedcontentcontenttypegenusspeciesfusobacteriumnucleatumnamedcontentnovelfunctionsofcelldivisionproteinsftsxandenvc
_version_ 1718427258106937344