ABSTRACT: Background: Aggregatibacter aphrophilus is a Gram-negative bacterium that is considered to be highly virulent in endocarditis and cerebral abscesses but has low virulence when it comes to periodontitis. One important mechanism for the virulence of A. aphrophilus is the serum resistance, which is partially obtained through the OmpA1 outer membrane protein. EmaA is an extracellular matrix protein adhesin that is found in the outer membrane of A. aphrophilus. This protein was earlier confirmed to contribute in autoaggregation and adhering of A. aphrophilus to human epithelial cells. Aim: The aim of our study has been to investigate if there is a possibility that EmaA contributes to serum resistance of A. aphrophilus, similar to OmpA1. Methods: To examine if EmaA contributes to serum resistance of A. aphrophilus, a serum killing assay was executed on four different strains of A. aphrophilus. These strains included a wildtype strain HK83, strains with a knocked out emaA and ompA1 gene, respectively and double mutant (emaA ompA1). The construction of the double mutant was done through a DNA-transformation procedure. A two- tailed T-test was used to calculate the data’s statistical significance. Results: As expected, the ompA1 mutant did not survive well in human serum. Interestingly, the ompA1 emaAdouble mutant had a clearly higher serum survival, suggesting that EmaA may negatively contribute to serum resistance. Conclusion: EmaA protein appears not to contribute to the serum resistance of A. aphrophilus but rather to serum sensitivity.
| Identifer | oai:union.ndltd.org:UPSALLA1/oai:DiVA.org:umu-202297 |
| Date | January 2022 |
| Creators | Shamoun, wourod, Alhaddad, Amal |
| Publisher | Umeå universitet, Tandläkarutbildning |
| Source Sets | DiVA Archive at Upsalla University |
| Language | English |
| Detected Language | English |
| Type | Student thesis, info:eu-repo/semantics/bachelorThesis, text |
| Format | application/pdf |
| Rights | info:eu-repo/semantics/openAccess |
Page generated in 0.0062 seconds