The Capsule Regulatory Network of <italic toggle="yes">Klebsiella pneumoniae</italic> Defined by density-TraDISort

ABSTRACT Klebsiella pneumoniae infections affect infants and the immunocompromised, and the recent emergence of hypervirulent and multidrug-resistant K. pneumoniae lineages is a critical health care concern. Hypervirulence in K. pneumoniae is mediated by several factors, including the overproduction...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Matthew J. Dorman, Theresa Feltwell, David A. Goulding, Julian Parkhill, Francesca L. Short
Formato:	article
Lenguaje:	EN
Publicado:	American Society for Microbiology 2018
Materias:	Klebsiella TraDIS capsular polysaccharide capsule regulation pathogenesis Microbiology QR1-502
Acceso en línea:	https://doaj.org/article/9ef885a8364843bfb6299b92f701c4b5
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:9ef885a8364843bfb6299b92f701c4b5
record_format	dspace
spelling	oai:doaj.org-article:9ef885a8364843bfb6299b92f701c4b52021-11-15T15:52:19ZThe Capsule Regulatory Network of <italic toggle="yes">Klebsiella pneumoniae</italic> Defined by density-TraDISort10.1128/mBio.01863-182150-7511https://doaj.org/article/9ef885a8364843bfb6299b92f701c4b52018-12-01T00:00:00Zhttps://journals.asm.org/doi/10.1128/mBio.01863-18https://doaj.org/toc/2150-7511ABSTRACT Klebsiella pneumoniae infections affect infants and the immunocompromised, and the recent emergence of hypervirulent and multidrug-resistant K. pneumoniae lineages is a critical health care concern. Hypervirulence in K. pneumoniae is mediated by several factors, including the overproduction of extracellular capsule. However, the full details of how K. pneumoniae capsule biosynthesis is achieved or regulated are not known. We have developed a robust and sensitive procedure to identify genes influencing capsule production, density-TraDISort, which combines density gradient centrifugation with transposon insertion sequencing. We have used this method to explore capsule regulation in two clinically relevant Klebsiella strains, K. pneumoniae NTUH-K2044 (capsule type K1) and K. pneumoniae ATCC 43816 (capsule type K2). We identified multiple genes required for full capsule production in K. pneumoniae, as well as putative suppressors of capsule in NTUH-K2044, and have validated the results of our screen with targeted knockout mutants. Further investigation of several of the K. pneumoniae capsule regulators identified—ArgR, MprA/KvrB, SlyA/KvrA, and the Sap ABC transporter—revealed effects on capsule amount and architecture, serum resistance, and virulence. We show that capsule production in K. pneumoniae is at the center of a complex regulatory network involving multiple global regulators and environmental cues and that the majority of capsule regulatory genes are located in the core genome. Overall, our findings expand our understanding of how capsule is regulated in this medically important pathogen and provide a technology that can be easily implemented to study capsule regulation in other bacterial species. IMPORTANCE Capsule production is essential for K. pneumoniae to cause infections, but its regulation and mechanism of synthesis are not fully understood in this organism. We have developed and applied a new method for genome-wide identification of capsule regulators. Using this method, many genes that positively or negatively affect capsule production in K. pneumoniae were identified, and we use these data to propose an integrated model for capsule regulation in this species. Several of the genes and biological processes identified have not previously been linked to capsule synthesis. We also show that the methods presented here can be applied to other species of capsulated bacteria, providing the opportunity to explore and compare capsule regulatory networks in other bacterial strains and species.Matthew J. DormanTheresa FeltwellDavid A. GouldingJulian ParkhillFrancesca L. ShortAmerican Society for MicrobiologyarticleKlebsiellaTraDIScapsular polysaccharidecapsule regulationpathogenesisMicrobiologyQR1-502ENmBio, Vol 9, Iss 6 (2018)
institution	DOAJ
collection	DOAJ
language	EN
topic	Klebsiella TraDIS capsular polysaccharide capsule regulation pathogenesis Microbiology QR1-502
spellingShingle	Klebsiella TraDIS capsular polysaccharide capsule regulation pathogenesis Microbiology QR1-502 Matthew J. Dorman Theresa Feltwell David A. Goulding Julian Parkhill Francesca L. Short The Capsule Regulatory Network of <italic toggle="yes">Klebsiella pneumoniae</italic> Defined by density-TraDISort
description	ABSTRACT Klebsiella pneumoniae infections affect infants and the immunocompromised, and the recent emergence of hypervirulent and multidrug-resistant K. pneumoniae lineages is a critical health care concern. Hypervirulence in K. pneumoniae is mediated by several factors, including the overproduction of extracellular capsule. However, the full details of how K. pneumoniae capsule biosynthesis is achieved or regulated are not known. We have developed a robust and sensitive procedure to identify genes influencing capsule production, density-TraDISort, which combines density gradient centrifugation with transposon insertion sequencing. We have used this method to explore capsule regulation in two clinically relevant Klebsiella strains, K. pneumoniae NTUH-K2044 (capsule type K1) and K. pneumoniae ATCC 43816 (capsule type K2). We identified multiple genes required for full capsule production in K. pneumoniae, as well as putative suppressors of capsule in NTUH-K2044, and have validated the results of our screen with targeted knockout mutants. Further investigation of several of the K. pneumoniae capsule regulators identified—ArgR, MprA/KvrB, SlyA/KvrA, and the Sap ABC transporter—revealed effects on capsule amount and architecture, serum resistance, and virulence. We show that capsule production in K. pneumoniae is at the center of a complex regulatory network involving multiple global regulators and environmental cues and that the majority of capsule regulatory genes are located in the core genome. Overall, our findings expand our understanding of how capsule is regulated in this medically important pathogen and provide a technology that can be easily implemented to study capsule regulation in other bacterial species. IMPORTANCE Capsule production is essential for K. pneumoniae to cause infections, but its regulation and mechanism of synthesis are not fully understood in this organism. We have developed and applied a new method for genome-wide identification of capsule regulators. Using this method, many genes that positively or negatively affect capsule production in K. pneumoniae were identified, and we use these data to propose an integrated model for capsule regulation in this species. Several of the genes and biological processes identified have not previously been linked to capsule synthesis. We also show that the methods presented here can be applied to other species of capsulated bacteria, providing the opportunity to explore and compare capsule regulatory networks in other bacterial strains and species.
format	article
author	Matthew J. Dorman Theresa Feltwell David A. Goulding Julian Parkhill Francesca L. Short
author_facet	Matthew J. Dorman Theresa Feltwell David A. Goulding Julian Parkhill Francesca L. Short
author_sort	Matthew J. Dorman
title	The Capsule Regulatory Network of <italic toggle="yes">Klebsiella pneumoniae</italic> Defined by density-TraDISort
title_short	The Capsule Regulatory Network of <italic toggle="yes">Klebsiella pneumoniae</italic> Defined by density-TraDISort
title_full	The Capsule Regulatory Network of <italic toggle="yes">Klebsiella pneumoniae</italic> Defined by density-TraDISort
title_fullStr	The Capsule Regulatory Network of <italic toggle="yes">Klebsiella pneumoniae</italic> Defined by density-TraDISort
title_full_unstemmed	The Capsule Regulatory Network of <italic toggle="yes">Klebsiella pneumoniae</italic> Defined by density-TraDISort
title_sort	capsule regulatory network of <italic toggle="yes">klebsiella pneumoniae</italic> defined by density-tradisort
publisher	American Society for Microbiology
publishDate	2018
url	https://doaj.org/article/9ef885a8364843bfb6299b92f701c4b5
work_keys_str_mv	AT matthewjdorman thecapsuleregulatorynetworkofitalictoggleyesklebsiellapneumoniaeitalicdefinedbydensitytradisort AT theresafeltwell thecapsuleregulatorynetworkofitalictoggleyesklebsiellapneumoniaeitalicdefinedbydensitytradisort AT davidagoulding thecapsuleregulatorynetworkofitalictoggleyesklebsiellapneumoniaeitalicdefinedbydensitytradisort AT julianparkhill thecapsuleregulatorynetworkofitalictoggleyesklebsiellapneumoniaeitalicdefinedbydensitytradisort AT francescalshort thecapsuleregulatorynetworkofitalictoggleyesklebsiellapneumoniaeitalicdefinedbydensitytradisort AT matthewjdorman capsuleregulatorynetworkofitalictoggleyesklebsiellapneumoniaeitalicdefinedbydensitytradisort AT theresafeltwell capsuleregulatorynetworkofitalictoggleyesklebsiellapneumoniaeitalicdefinedbydensitytradisort AT davidagoulding capsuleregulatorynetworkofitalictoggleyesklebsiellapneumoniaeitalicdefinedbydensitytradisort AT julianparkhill capsuleregulatorynetworkofitalictoggleyesklebsiellapneumoniaeitalicdefinedbydensitytradisort AT francescalshort capsuleregulatorynetworkofitalictoggleyesklebsiellapneumoniaeitalicdefinedbydensitytradisort
_version_	1718427292246474752

The Capsule Regulatory Network of <italic toggle="yes">Klebsiella pneumoniae</italic> Defined by density-TraDISort

Ejemplares similares