Fitness cost and excision rate of the conjugative transposon Tn916

Abstract

Dental infections are getting more difficult to treat because of the increasing amount of antibiotic resistant oral bacteria. A bacterium can acquire resistance by horizontal gene transfer, this allows a bacterial population to acquire antibiotic resistance genes at a great rate. Occasionally, newly acquired resistance can reduce bacterial fitness. However, bacteria can evolve quickly to compensate for any fitness loss. Mobile genetic elements are genetic elements capable of translocation in the same genome, or move between bacterial species or cross bacterial populations. Mobile genetic elements are important from a clinical point of view because they can mediate the transfer of antibiotic resistance. Tn916 is a type of mobile genetic element which can be transferred into a wide range of bacterial phyla. This study aimed to investigate the fitness cost of newly acquired Tn916 in Enterococcus faecium through investigation of growth curves of different strains of E. faecium with and without Tn916. This study will also investigate the excision rate of Tn916, using ddPCR.