ArticleGut pathogens2014
Phase-variable restriction/modification systems are required for Helicobacter pylori colonization.
Article in Gut pathogens, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 23 papers.
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Who cites it
23 citing papers in PubMed, 29 citations in OpenAlex.
- How to Unmask an Unknown: The Restriction-Modification SystemInternational journal of molecular sciences · 2026Article
- Epigenetic regulation in prokaryotes: transcriptional and phenotypic outcomes of DNA methyltransferase activity.FEMS microbiology reviews · 2026Review
- Comprehensive profiling of genomic invertons in defined gut microbial community reveals associations with intestinal colonization and surface adhesion.Microbiome · 2025Article
- Changes in potential pathogenicity-associated proteins ofFrontiers in microbiology · 2025Article
- Deep learning revealed the distribution and evolution patterns for invertible promoters across bacterial lineages.Nucleic acids research · 2024Article
- TheJournal of bacteriology · 2024Article
- Regulation of Helicobacter pylori Urease and Acetone Carboxylase Genes by Nitric Oxide and the CrdRS Two-Component System.Microbiology spectrum · 2023Article
- Bacterial DNA methyltransferase: A key to the epigenetic world with lessons learned from proteobacteria.Frontiers in microbiology · 2023Review
- Biomarker Characterization and Prediction of Virulence and Antibiotic Resistance fromBiomolecules · 2022Review
- Review
- Article
- Regulator-dependent temporal dynamics of a restriction-modification system's gene expression upon entering new host cells: single-cell and population studies.Nucleic acids research · 2021Article
- A Bacterial Epigenetic Switch in Non-typeableFrontiers in cellular and infection microbiology · 2020Article
- Transcriptome analyses of cells carrying the Type II Csp231I restriction-modification system reveal cross-talk between two unrelated transcription factors: C protein and the Rac prophage repressor.Nucleic acids research · 2019Article
- Single-molecule sequencing detection of N6-methyladenine in microbial reference materials.Nature communications · 2019Article
- Invertible promoters mediate bacterial phase variation, antibiotic resistance, and host adaptation in the gut.Science (New York, N.Y.) · 2019Article
- Phasevarions of Bacterial Pathogens: Methylomics Sheds New Light on Old Enemies.Trends in microbiology · 2018Review
- Methylomic and phenotypic analysis of the ModH5 phasevarion of Helicobacter pylori.Scientific reports · 2017Article
- ModA2 Phasevarion Switching in Nontypeable Haemophilus influenzae Increases the Severity of Experimental Otitis Media.The Journal of infectious diseases · 2016Article
- PCR Based Detection of Phase Variable Genes in Pakistani Based Clinical Helicobacter pylori Strains.Jundishapur journal of microbiology · 2016Article
Corrections and comments
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Authors and funding
5 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundOne mechanism utilized by bacterial pathogens for host adaptation and immune evasion is the generation of phenotypic diversity by the phasevarion that results from the differential expression of a suite of genes regulated by the activity of a phase-variable methyltransferase within a restriction modification (RM) system. Phasevarions are active in Helicobacter pylori, however there have been no studies investigating the significance of phase-variable RM systems on host colonization.
methodsTwo mutant types incapable of phase variation were constructed; a clean deletion mutant ('DEL') and a mutant ('ON') where the homopolymeric repeat was replaced with a non-repeat synonymous sequence, resulting in expression of the full-length protein. The resulting mutants were assessed for their colonisation ability in the mouse model.
resultsFive phase-variable genes encoding either methyltransferases or members of RM systems were found in H. pylori OND79. Our mutants fell into three categories; 1, those with little effect on colonization, 2, those where expression of the full-length protein was detrimental, 3, those where both mutations were detrimental.
conclusionsOur results demonstrated that phase-variable methyltransferases are critical to H. pylori colonization, suggesting that genome methylation and generation of epigenetic diversity is important for colonization and pathogenesis. The third category of mutants suggests that differential genome methylation status of H. pylori cell populations, achieved by the phasevarion, is essential for host adaptation. Studies of phase-variable RM mutants falling in the two other categories, not strictly required for colonization, represent a future perspective to investigate the role of phasevarion in persistence of H. pylori.
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