Bioinformatics and Functional Assessment of Toxin-Antitoxin Systems in Staphylococcus aureus

• Published in: Toxins Vol. 10; no. 11; p. 473
• Main Authors: Habib, Gul, Zhu, Qing, Sun, Baolin
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 14.11.2018; MDPI
• Subjects: Antitoxins; Bacteria; Bacterial Toxins - genetics; Bacterial Toxins - immunology; Bioinformatics; Cell size; Cell walls; Communication; Computational Biology; E coli; Escherichia coli; Escherichia coli - genetics; Escherichia coli - immunology; Genes; Genomes; HigBA; Homology; Hospitals; Mycobacterium - genetics; Mycobacterium - immunology; Nosocomial infection; Pathogenesis; Pathogenicity; Pathogenicity islands; Pathogens; Proteins; Regeneration; Salmonella; Septation; Staphylococcus aureus; Staphylococcus aureus - genetics; Staphylococcus aureus - immunology; Streptococcus infections; toxin-antitoxin systems; Toxin-Antitoxin Systems - genetics; Toxins; Toxins and antitoxins; Transcription; Virulence; HigBA; toxin-antitoxin systems; pathogenicity islands; Staphylococcus aureus
• ISSN: 2072-6651; 2072-6651
• DOI: 10.3390/toxins10110473

is a nosocomial pathogen that can cause chronic to persistent infections. Among different mediators of pathogenesis, toxin-antitoxin (TA) systems are emerging as the most prominent. These systems are frequently studied in and species but rarely explored in . In the present study, we thoroughly analyzed the genome and screened all possible TA systems using the Rasta bacteria and toxin-antitoxin database. We further searched and TA homologs and selected 67 TA loci as putative TA systems in . The host inhibition of growth (HigBA) TA family was predominantly detected in . In addition, we detected seven pathogenicity islands in the genome that are enriched with virulence genes and contain 26 out of 67 TA systems. We ectopically expressed multiple TA genes in and that exhibited bacteriostatic and bactericidal effects on cell growth. The type I Fst toxin created holes in the cell wall while the TxpA toxin reduced cell size and induced cell wall septation. Besides, we identified a new TA system whose antitoxin functions as a transcriptional autoregulator while the toxin functions as an inhibitor of autoregulation. Altogether, this study provides a plethora of new as well as previously known TA systems that will revitalize the research on TA systems.