The SpxA1-TenA toxin-antitoxin system regulates epigenetic variations of Streptococcus pneumoniae by targeting protein synthesis.

Human pathogen Streptococcus pneumoniae forms multiple epigenetically and phenotypically distinct intra-populations by invertase PsrA-driven inversions of DNA methyltransferase hsdS genes in the colony opacity-determinant (cod) locus. As manifested by phase switch between opaque and transparent colo...

Full description

Saved in:
Bibliographic Details
Main Authors: Shaomeng Wang, Xiu-Yuan Li, Mengran Zhu, Haiteng Deng, Juanjuan Wang, Jing-Ren Zhang
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2024-12-01
Series:PLoS Pathogens
Online Access:https://doi.org/10.1371/journal.ppat.1012801
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1841533260305268736
author Shaomeng Wang
Xiu-Yuan Li
Mengran Zhu
Haiteng Deng
Juanjuan Wang
Jing-Ren Zhang
author_facet Shaomeng Wang
Xiu-Yuan Li
Mengran Zhu
Haiteng Deng
Juanjuan Wang
Jing-Ren Zhang
author_sort Shaomeng Wang
collection DOAJ
description Human pathogen Streptococcus pneumoniae forms multiple epigenetically and phenotypically distinct intra-populations by invertase PsrA-driven inversions of DNA methyltransferase hsdS genes in the colony opacity-determinant (cod) locus. As manifested by phase switch between opaque and transparent colonies, different genome methylation patterns or epigenomes confer pathogenesis-associated traits, but it is unknown how the pathogen controls the hsdS inversion orientations. Here, we report our finding of the SpxA1-TenA toxin-antitoxin (TA) system that regulates the orientations of hsdS inversions, and thereby bacterial epigenome and associated traits (e.g., colony opacity) by targeting pneumococcal protein synthesis. SpxA1 and TenA were found to constitute a highly conserved type II TA system in S. pneumoniae, primarily based on the observation that overexpressing toxin TenA led to growth arrest in E. coli and enhanced autolysis in S. pneumoniae, and the antitoxin SpxA1 repressed the transcription of the spxA1-tenA operon. When the transcription of tenA was de-repressed by a spontaneous AT di-nucleotide insertion/deletion in the promoter region of the spxA1-tenA operon, TenA bound to the ribosome maturation factor RimM, and thereby reduced the cellular level of alternative sigma factor ComX (known for the activation of natural transformation-associated genes). Attenuation of ComX expression in turn enhanced the transcription of the invertase gene psrA, which favored the formation of the transparent colony phase-associated hsdS allelic configurations in the cod locus. Phenotypically, moderate expression of TenA dramatically reshaped pneumococcal epigenome and colony opacity. Because spontaneous variations frequently occur during bacterial growth in the number of the AT di-nucleotides in the promoter region of the spxA1-tenA operon, this locus acts as a programmed genetic switch that generates pneumococcal subpopulations with epigenetic and phenotypic diversity.
format Article
id doaj-art-bcb4d350b4b24a63844b450f379bc0e2
institution Kabale University
issn 1553-7366
1553-7374
language English
publishDate 2024-12-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Pathogens
spelling doaj-art-bcb4d350b4b24a63844b450f379bc0e22025-01-17T05:31:03ZengPublic Library of Science (PLoS)PLoS Pathogens1553-73661553-73742024-12-012012e101280110.1371/journal.ppat.1012801The SpxA1-TenA toxin-antitoxin system regulates epigenetic variations of Streptococcus pneumoniae by targeting protein synthesis.Shaomeng WangXiu-Yuan LiMengran ZhuHaiteng DengJuanjuan WangJing-Ren ZhangHuman pathogen Streptococcus pneumoniae forms multiple epigenetically and phenotypically distinct intra-populations by invertase PsrA-driven inversions of DNA methyltransferase hsdS genes in the colony opacity-determinant (cod) locus. As manifested by phase switch between opaque and transparent colonies, different genome methylation patterns or epigenomes confer pathogenesis-associated traits, but it is unknown how the pathogen controls the hsdS inversion orientations. Here, we report our finding of the SpxA1-TenA toxin-antitoxin (TA) system that regulates the orientations of hsdS inversions, and thereby bacterial epigenome and associated traits (e.g., colony opacity) by targeting pneumococcal protein synthesis. SpxA1 and TenA were found to constitute a highly conserved type II TA system in S. pneumoniae, primarily based on the observation that overexpressing toxin TenA led to growth arrest in E. coli and enhanced autolysis in S. pneumoniae, and the antitoxin SpxA1 repressed the transcription of the spxA1-tenA operon. When the transcription of tenA was de-repressed by a spontaneous AT di-nucleotide insertion/deletion in the promoter region of the spxA1-tenA operon, TenA bound to the ribosome maturation factor RimM, and thereby reduced the cellular level of alternative sigma factor ComX (known for the activation of natural transformation-associated genes). Attenuation of ComX expression in turn enhanced the transcription of the invertase gene psrA, which favored the formation of the transparent colony phase-associated hsdS allelic configurations in the cod locus. Phenotypically, moderate expression of TenA dramatically reshaped pneumococcal epigenome and colony opacity. Because spontaneous variations frequently occur during bacterial growth in the number of the AT di-nucleotides in the promoter region of the spxA1-tenA operon, this locus acts as a programmed genetic switch that generates pneumococcal subpopulations with epigenetic and phenotypic diversity.https://doi.org/10.1371/journal.ppat.1012801
spellingShingle Shaomeng Wang
Xiu-Yuan Li
Mengran Zhu
Haiteng Deng
Juanjuan Wang
Jing-Ren Zhang
The SpxA1-TenA toxin-antitoxin system regulates epigenetic variations of Streptococcus pneumoniae by targeting protein synthesis.
PLoS Pathogens
title The SpxA1-TenA toxin-antitoxin system regulates epigenetic variations of Streptococcus pneumoniae by targeting protein synthesis.
title_full The SpxA1-TenA toxin-antitoxin system regulates epigenetic variations of Streptococcus pneumoniae by targeting protein synthesis.
title_fullStr The SpxA1-TenA toxin-antitoxin system regulates epigenetic variations of Streptococcus pneumoniae by targeting protein synthesis.
title_full_unstemmed The SpxA1-TenA toxin-antitoxin system regulates epigenetic variations of Streptococcus pneumoniae by targeting protein synthesis.
title_short The SpxA1-TenA toxin-antitoxin system regulates epigenetic variations of Streptococcus pneumoniae by targeting protein synthesis.
title_sort spxa1 tena toxin antitoxin system regulates epigenetic variations of streptococcus pneumoniae by targeting protein synthesis
url https://doi.org/10.1371/journal.ppat.1012801
work_keys_str_mv AT shaomengwang thespxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis
AT xiuyuanli thespxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis
AT mengranzhu thespxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis
AT haitengdeng thespxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis
AT juanjuanwang thespxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis
AT jingrenzhang thespxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis
AT shaomengwang spxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis
AT xiuyuanli spxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis
AT mengranzhu spxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis
AT haitengdeng spxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis
AT juanjuanwang spxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis
AT jingrenzhang spxa1tenatoxinantitoxinsystemregulatesepigeneticvariationsofstreptococcuspneumoniaebytargetingproteinsynthesis