Transcriptional Repressor PtvR Regulates Phenotypic Tolerance to Vancomycin in Streptococcus pneumoniae.

Détails

ID Serval
serval:BIB_BDA763F184C7
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Transcriptional Repressor PtvR Regulates Phenotypic Tolerance to Vancomycin in Streptococcus pneumoniae.
Périodique
Journal of bacteriology
Auteur⸱e⸱s
Liu X., Li J.W., Feng Z., Luo Y., Veening J.W., Zhang J.R.
ISSN
1098-5530 (Electronic)
ISSN-L
0021-9193
Statut éditorial
Publié
Date de publication
15/07/2017
Peer-reviewed
Oui
Volume
199
Numéro
14
Pages
UNSP e00054-17
Langue
anglais
Notes
Publication types: Journal Article
Publication Status: epublish
Résumé
Reversible or phenotypic tolerance to antibiotics within microbial populations has been implicated in treatment failure of chronic infections and development of persister cells. However, the molecular mechanisms regulating phenotypic drug tolerance are largely unknown. In this study, we identified a four-gene operon in Streptococcus pneumoniae that contributes to phenotypic tolerance to vancomycin (ptv). RNA sequencing, quantiative reverse transcriptase PCR, and transcriptional luciferase reporter experiments revealed that transcription of the ptv operon (consisting of ptvR, ptvA, ptvB, and ptvC) is induced by exposure to vancomycin. Further investigation showed that transcription of the ptv operon is repressed by PtvR, a PadR family repressor. Transcriptional induction of the ptv operon by vancomycin was achieved by transcriptional derepression of this locus, which was mediated by PtvR. Importantly, fully derepressing ptvABC by deleting ptvR or overexpressing the ptv operon with an exogenous promoter significantly enhanced vancomycin tolerance. Gene deletion analysis revealed that PtvA, PtvB, and PtvC are all required for the PtvR-regulated phenotypic tolerance to vancomycin. Finally, the results of an electrophoretic mobility shift assay with recombinant PtvR showed that PtvR represses the transcription of the ptv operon by binding to two palindromic sequences within the ptv promoter. Together, the ptv locus represents an inducible system in S. pneumoniae in response to stressful conditions, including those caused by antibiotics.IMPORTANCE Reversible or phenotypic tolerance to antibiotics within microbial populations is associated with treatment failure of bacterial diseases, but the underlying mechanisms regulating phenotypic drug tolerance remain obscure. This study reports our finding of a multigene locus that contributes to inducible tolerance to vancomycin in Streptococcus pneumoniae, an important opportunistic human pathogen. The vancomycin tolerance phenotype depends on the PtvR transcriptional repressor and three predicted membrane-associated proteins encoded by the ptv locus. This represents the first example of a gene locus in S. pneumoniae that is responsible for antibiotic tolerance and has important implications for further understanding bacterial responses and phenotypic tolerance to antibiotic treatment in this and other pathogens.

Mots-clé
Anti-Bacterial Agents/pharmacology, Bacterial Proteins/genetics, Bacterial Proteins/metabolism, Drug Resistance, Bacterial/genetics, Gene Expression Regulation, Bacterial/physiology, Streptococcus pneumoniae/drug effects, Streptococcus pneumoniae/genetics, Streptococcus pneumoniae/metabolism, Transcription Factors/genetics, Transcription Factors/metabolism, Vancomycin/pharmacology, PadR family regulator, Streptococcus pneumoniae, gene regulation, phenotypic tolerance, transcriptional derepression, vancomycin
Pubmed
Web of science
Open Access
Oui
Création de la notice
16/05/2017 16:25
Dernière modification de la notice
20/08/2019 15:31
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