Genetic diversity among Canadian isolates of penicillin-resistant Streptococcus pneumoniae and characterization of penicillin-binding protein 1A, 2B and 2X mutations
dc.contributor.author | Nichol, Kimberly Anne | en_US |
dc.date.accessioned | 2007-07-12T17:51:14Z | |
dc.date.available | 2007-07-12T17:51:14Z | |
dc.date.issued | 2001-01-01T00:00:00Z | en_US |
dc.degree.discipline | Medical Microbiology | en_US |
dc.degree.level | Master of Science (M.Sc.) | en_US |
dc.description.abstract | Increases in the prevalence of penicillin-nonsusceptible ' Streptococcus pneumoniae' can be attributed to the acquisition of altered penicillin-binding protein (PBP) genes and to the geographic spread of genetically related isolates with elevated B-lactam minimum inhibitory concentrations (MICs). The objective of this thesis was to characterize ' pbp1a, pbp2b' and 'pbp2x' mutations in Canadian isolates of penicillin-nonsusceptible 'S. pneumoniae' and to evaluate the relationship between genetic diversity and penicillin susceptibility as it pertains to the dissemination of resistance. Both pulsed-field gel electrophoresis (PFGE) and arbitrarily-primed PCR (AP-PCR) revealed homogeneity amongst penicillin-resistant isolates and exclusive heterogeneity amongst penicillin-intermediate and penicillin-susceptible isolates. Four penicillin-resistant isolates with homogenous typing profiles serotyped 19F, 23F and 14, indicating several instances of probable capsular serotype switching. Sequence analysis of the penicillin-binding domains of ' pbp1a, pbp2b' and 'pbp2x' revealed identical nucleotide and amino acid substitution patterns in all isolates with penicillin MICs >=1 [mu]g/ml. (Abstract shortened by UMI.) | en_US |
dc.format.extent | 11920000 bytes | |
dc.format.extent | 184 bytes | |
dc.format.mimetype | application/pdf | |
dc.format.mimetype | text/plain | |
dc.identifier.uri | http://hdl.handle.net/1993/2620 | |
dc.language.iso | eng | en_US |
dc.rights | open access | en_US |
dc.title | Genetic diversity among Canadian isolates of penicillin-resistant Streptococcus pneumoniae and characterization of penicillin-binding protein 1A, 2B and 2X mutations | en_US |
dc.type | master thesis | en_US |