Cargando…
Characterization of the relationship between integrase, excisionase and antirepressor activities associated with a superinfecting Shiga toxin encoding bacteriophage
Shigatoxigenic Escherichia coli emerged as new food borne pathogens in the early 1980s, primarily driven by the dispersal of Shiga toxin-encoding lambdoid bacteriophages. At least some of these Stx phages display superinfection phenotypes, which differ significantly from lambda phage itself, driving...
Autores principales: | , , , , |
---|---|
Formato: | Texto |
Lenguaje: | English |
Publicado: |
Oxford University Press
2011
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3064807/ https://www.ncbi.nlm.nih.gov/pubmed/21062824 http://dx.doi.org/10.1093/nar/gkq923 |
_version_ | 1782200924362506240 |
---|---|
author | Fogg, P. C. M. Rigden, D. J. Saunders, J. R. McCarthy, A. J. Allison, H. E. |
author_facet | Fogg, P. C. M. Rigden, D. J. Saunders, J. R. McCarthy, A. J. Allison, H. E. |
author_sort | Fogg, P. C. M. |
collection | PubMed |
description | Shigatoxigenic Escherichia coli emerged as new food borne pathogens in the early 1980s, primarily driven by the dispersal of Shiga toxin-encoding lambdoid bacteriophages. At least some of these Stx phages display superinfection phenotypes, which differ significantly from lambda phage itself, driving through in situ recombination further phage evolution, increasing host range and potentially increasing the host's pathogenic profile. Here, increasing levels of Stx phage Φ24(B) integrase expression in multiple lysogen cultures are demonstrated along with apparently negligible repression of integrase expression by the cognate CI repressor. The Φ24(B) int transcription start site and promoter region were identified and found to differ from in silico predictions. The unidirectional activity of this integrase was determined in an in situ, inducible tri-partite reaction. This indicated that Φ24(B) must encode a novel directionality factor that is controlling excision events during prophage induction. This excisionase was subsequently identified and characterized through complementation experiments. In addition, the previous proposal that a putative antirepressor was responsible for the lack of immunity to superinfection through inactivation of CI has been revisited and a new hypothesis involving the role of this protein in promoting efficient induction of the Φ24(B) prophage is proposed. |
format | Text |
id | pubmed-3064807 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2011 |
publisher | Oxford University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-30648072011-03-28 Characterization of the relationship between integrase, excisionase and antirepressor activities associated with a superinfecting Shiga toxin encoding bacteriophage Fogg, P. C. M. Rigden, D. J. Saunders, J. R. McCarthy, A. J. Allison, H. E. Nucleic Acids Res Genome Integrity, Repair and Replication Shigatoxigenic Escherichia coli emerged as new food borne pathogens in the early 1980s, primarily driven by the dispersal of Shiga toxin-encoding lambdoid bacteriophages. At least some of these Stx phages display superinfection phenotypes, which differ significantly from lambda phage itself, driving through in situ recombination further phage evolution, increasing host range and potentially increasing the host's pathogenic profile. Here, increasing levels of Stx phage Φ24(B) integrase expression in multiple lysogen cultures are demonstrated along with apparently negligible repression of integrase expression by the cognate CI repressor. The Φ24(B) int transcription start site and promoter region were identified and found to differ from in silico predictions. The unidirectional activity of this integrase was determined in an in situ, inducible tri-partite reaction. This indicated that Φ24(B) must encode a novel directionality factor that is controlling excision events during prophage induction. This excisionase was subsequently identified and characterized through complementation experiments. In addition, the previous proposal that a putative antirepressor was responsible for the lack of immunity to superinfection through inactivation of CI has been revisited and a new hypothesis involving the role of this protein in promoting efficient induction of the Φ24(B) prophage is proposed. Oxford University Press 2011-03 2010-11-08 /pmc/articles/PMC3064807/ /pubmed/21062824 http://dx.doi.org/10.1093/nar/gkq923 Text en © The Author(s) 2010. Published by Oxford University Press. http://creativecommons.org/licenses/by-nc/2.5 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.5), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Genome Integrity, Repair and Replication Fogg, P. C. M. Rigden, D. J. Saunders, J. R. McCarthy, A. J. Allison, H. E. Characterization of the relationship between integrase, excisionase and antirepressor activities associated with a superinfecting Shiga toxin encoding bacteriophage |
title | Characterization of the relationship between integrase, excisionase and antirepressor activities associated with a superinfecting Shiga toxin encoding bacteriophage |
title_full | Characterization of the relationship between integrase, excisionase and antirepressor activities associated with a superinfecting Shiga toxin encoding bacteriophage |
title_fullStr | Characterization of the relationship between integrase, excisionase and antirepressor activities associated with a superinfecting Shiga toxin encoding bacteriophage |
title_full_unstemmed | Characterization of the relationship between integrase, excisionase and antirepressor activities associated with a superinfecting Shiga toxin encoding bacteriophage |
title_short | Characterization of the relationship between integrase, excisionase and antirepressor activities associated with a superinfecting Shiga toxin encoding bacteriophage |
title_sort | characterization of the relationship between integrase, excisionase and antirepressor activities associated with a superinfecting shiga toxin encoding bacteriophage |
topic | Genome Integrity, Repair and Replication |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3064807/ https://www.ncbi.nlm.nih.gov/pubmed/21062824 http://dx.doi.org/10.1093/nar/gkq923 |
work_keys_str_mv | AT foggpcm characterizationoftherelationshipbetweenintegraseexcisionaseandantirepressoractivitiesassociatedwithasuperinfectingshigatoxinencodingbacteriophage AT rigdendj characterizationoftherelationshipbetweenintegraseexcisionaseandantirepressoractivitiesassociatedwithasuperinfectingshigatoxinencodingbacteriophage AT saundersjr characterizationoftherelationshipbetweenintegraseexcisionaseandantirepressoractivitiesassociatedwithasuperinfectingshigatoxinencodingbacteriophage AT mccarthyaj characterizationoftherelationshipbetweenintegraseexcisionaseandantirepressoractivitiesassociatedwithasuperinfectingshigatoxinencodingbacteriophage AT allisonhe characterizationoftherelationshipbetweenintegraseexcisionaseandantirepressoractivitiesassociatedwithasuperinfectingshigatoxinencodingbacteriophage |