Staphylococcus aureus toxins: expression and control
<p><em>Staphylococcus aureus</em> was discovered in 1880 by the Scottish surgeon Sir Alexander Ogston. Its ability to utilise a panoply of secreted and cell associated virulence factors, combined with an ability to rapidly adapt to antibiotic selective pressure, has led it to becom...
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| Format: | Thesis |
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2009
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| _version_ | 1797089244973367296 |
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| author | Collins, J |
| author_facet | Collins, J |
| author_sort | Collins, J |
| collection | OXFORD |
| description | <p><em>Staphylococcus aureus</em> was discovered in 1880 by the Scottish surgeon Sir Alexander Ogston. Its ability to utilise a panoply of secreted and cell associated virulence factors, combined with an ability to rapidly adapt to antibiotic selective pressure, has led it to become one of the most important Gram positive pathogens of our time. It plays a significant role in chronic diseases such as eczema, as well as the acute and potentially life threatening conditions toxic shock syndrome (TSS), meningitis, pneumonia and staphylococcal scalded skin syndrome (SSSS) to name just a few. Its presence in hospitals is endemic in many countries, where methicillin resistant <em>S. aureus</em> (MRSA) strains have earned the 'superbug' moniker.</p> <p>Using a large, well-defined, clinical strain collection in combination with isogenic lab strains, this study endeavored to characterise the genetic factors associated with <em>S. aureus</em> toxicity, and identify novel means of controlling toxin expression.</p> <p>We found that:</p> <p>• A broad range of toxicities exists among <em>S. aureus</em> strains, that the beta- and delta-haemolysins are involved, and that hospital acquired-MRSA (HA-MRSA) strains are less toxic than MSSA or community acquired-MRSA (CA-MRSA). <p>• NaCl and the emollient Oilatum downregulate toxin expression.</p> <p>• The <em>mec</em>A gene, conferring methicillin resistance, mediates mutation rates.</p> <p>• The large type II SCC<em>mec</em> element of HA-MRSA confers a significant metabolic burden which is mitigated by the down regulation of toxins.</p> <p>• The smaller type IV SCC<em>mec</em> element of CA-MRSA does not confer a significant metabolic burden, enabling CA-MRSA to utilise their full arsenal of virulence factors.</p></p> |
| first_indexed | 2024-03-07T03:01:35Z |
| format | Thesis |
| id | oxford-uuid:b1226c5f-aedc-413f-8af4-9fb619c2de24 |
| institution | University of Oxford |
| last_indexed | 2024-03-07T03:01:35Z |
| publishDate | 2009 |
| record_format | dspace |
| spelling | oxford-uuid:b1226c5f-aedc-413f-8af4-9fb619c2de242022-03-27T04:01:45ZStaphylococcus aureus toxins: expression and controlThesishttp://purl.org/coar/resource_type/c_db06uuid:b1226c5f-aedc-413f-8af4-9fb619c2de24Polonsky Theses Digitisation Project2009Collins, J<p><em>Staphylococcus aureus</em> was discovered in 1880 by the Scottish surgeon Sir Alexander Ogston. Its ability to utilise a panoply of secreted and cell associated virulence factors, combined with an ability to rapidly adapt to antibiotic selective pressure, has led it to become one of the most important Gram positive pathogens of our time. It plays a significant role in chronic diseases such as eczema, as well as the acute and potentially life threatening conditions toxic shock syndrome (TSS), meningitis, pneumonia and staphylococcal scalded skin syndrome (SSSS) to name just a few. Its presence in hospitals is endemic in many countries, where methicillin resistant <em>S. aureus</em> (MRSA) strains have earned the 'superbug' moniker.</p> <p>Using a large, well-defined, clinical strain collection in combination with isogenic lab strains, this study endeavored to characterise the genetic factors associated with <em>S. aureus</em> toxicity, and identify novel means of controlling toxin expression.</p> <p>We found that:</p> <p>• A broad range of toxicities exists among <em>S. aureus</em> strains, that the beta- and delta-haemolysins are involved, and that hospital acquired-MRSA (HA-MRSA) strains are less toxic than MSSA or community acquired-MRSA (CA-MRSA). <p>• NaCl and the emollient Oilatum downregulate toxin expression.</p> <p>• The <em>mec</em>A gene, conferring methicillin resistance, mediates mutation rates.</p> <p>• The large type II SCC<em>mec</em> element of HA-MRSA confers a significant metabolic burden which is mitigated by the down regulation of toxins.</p> <p>• The smaller type IV SCC<em>mec</em> element of CA-MRSA does not confer a significant metabolic burden, enabling CA-MRSA to utilise their full arsenal of virulence factors.</p></p> |
| spellingShingle | Collins, J Staphylococcus aureus toxins: expression and control |
| title | Staphylococcus aureus toxins: expression and control |
| title_full | Staphylococcus aureus toxins: expression and control |
| title_fullStr | Staphylococcus aureus toxins: expression and control |
| title_full_unstemmed | Staphylococcus aureus toxins: expression and control |
| title_short | Staphylococcus aureus toxins: expression and control |
| title_sort | staphylococcus aureus toxins expression and control |
| work_keys_str_mv | AT collinsj staphylococcusaureustoxinsexpressionandcontrol |