Relationship between virulence factor and toxin antitoxin system in enterococcus
Toxin-antitoxin system is a regulatory system where two sets of genes encodes the toxin and its corresponding antitoxin. There is no documented study that showed the association between virulence genes and TA system in Enterococcus faecium and Enterococcus faecalis. For this purpose,the prev...
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my.upm.eprints.753562019-11-21T08:18:26Z http://psasir.upm.edu.my/id/eprint/75356/ Relationship between virulence factor and toxin antitoxin system in enterococcus Soheili, Sara Toxin-antitoxin system is a regulatory system where two sets of genes encodes the toxin and its corresponding antitoxin. There is no documented study that showed the association between virulence genes and TA system in Enterococcus faecium and Enterococcus faecalis. For this purpose,the prevalence of TA systems in independently isolated clinical isolates of E. faecium and E. faecalis were determined, then the dominant TA systems were identified, different virulence genes in E. faecium and E. faecalisare surveyed and subsequently the level of expression of virulence and TA genes in normal and stress conditions were determined and finally their association with TA genes are defined.Remarkably, sequences for one particular TA pair, mazEF and higBATA systems, were present on plasmid and chromosome of all E. faecium andE. faecalis strains, respectively. Additionally, toxin transcript expression levels were increased when bacteria were grown under stressful conditions. The pilB, fms8, efaAfm and sgrA are the most prevalent virulence genes in E. faecium and E. faecalis. These virulence genes were reported for first time in E. Faecalis, so this study demonstrated the importance of horizontal transformation in E. faecium and E. Faecalis. Peptide nucleic acid assay demonstrated with silencing of mazF by anti-mazF PNA a decrease of expression level of virulence genes were observed. The findings showed association between TA systems and virulence factor. The mazEF TA locion plasmid and higBA TA genes on chromosome of all E. faecium and E. faecalis were dominant. Also, there was decreasing of expression of virulence genes in presence of anti mazF-PNA. Therefore, it is recommended that mazEF TA systems are potent and sensitive targets in of all E. faecium and E.Faecalis. Hence, deactivation of the toxin proteins in the mazEF TA system should be investigated further as an effective antibacterial strategy against this bacterium. 2014-09 Thesis NonPeerReviewed text en http://psasir.upm.edu.my/id/eprint/75356/1/FPSK%28M%29%202014%206%20IR.pdf Soheili, Sara (2014) Relationship between virulence factor and toxin antitoxin system in enterococcus. Masters thesis, Universiti Putra Malaysia. Enterococcus - genetics Virulence - physiology Virulence - genetics |
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Enterococcus - genetics Virulence - physiology Virulence - genetics Soheili, Sara Relationship between virulence factor and toxin antitoxin system in enterococcus |
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Toxin-antitoxin system is a regulatory system where two sets of genes
encodes the toxin and its corresponding antitoxin. There is no documented
study that showed the association between virulence genes and TA system in
Enterococcus faecium and Enterococcus faecalis.
For this purpose,the prevalence of TA systems in independently isolated
clinical isolates of E. faecium and E. faecalis were determined, then the
dominant TA systems were identified, different virulence genes in E. faecium
and E. faecalisare surveyed and subsequently the level of expression of
virulence and TA genes in normal and stress conditions were determined
and finally their association with TA genes are defined.Remarkably,
sequences for one particular TA pair, mazEF and higBATA systems, were
present on plasmid and chromosome of all E. faecium andE. faecalis strains,
respectively. Additionally, toxin transcript expression levels were increased
when bacteria were grown under stressful conditions. The pilB, fms8, efaAfm
and sgrA are the most prevalent virulence genes in E. faecium and E. faecalis.
These virulence genes were reported for first time in E. Faecalis, so this study
demonstrated the importance of horizontal transformation in E. faecium
and E. Faecalis. Peptide nucleic acid assay demonstrated with silencing of
mazF by anti-mazF PNA a decrease of expression level of virulence genes
were observed. The findings showed association between TA systems and
virulence factor. The mazEF TA locion plasmid and higBA TA genes on
chromosome of all E. faecium and E. faecalis were dominant. Also, there was
decreasing of expression of virulence genes in presence of anti mazF-PNA.
Therefore, it is recommended that mazEF
TA systems are potent and sensitive targets in of all E. faecium and E.Faecalis.
Hence, deactivation of the toxin proteins in the mazEF TA system should be
investigated further as an effective antibacterial strategy against this
bacterium. |
format |
Thesis |
author |
Soheili, Sara |
author_facet |
Soheili, Sara |
author_sort |
Soheili, Sara |
title |
Relationship between virulence factor and toxin antitoxin system in enterococcus |
title_short |
Relationship between virulence factor and toxin antitoxin system in enterococcus |
title_full |
Relationship between virulence factor and toxin antitoxin system in enterococcus |
title_fullStr |
Relationship between virulence factor and toxin antitoxin system in enterococcus |
title_full_unstemmed |
Relationship between virulence factor and toxin antitoxin system in enterococcus |
title_sort |
relationship between virulence factor and toxin antitoxin system in enterococcus |
publishDate |
2014 |
url |
http://psasir.upm.edu.my/id/eprint/75356/1/FPSK%28M%29%202014%206%20IR.pdf http://psasir.upm.edu.my/id/eprint/75356/ |
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13.18916 |