Overview: Delivering Antibiotic Susceptibility in vivo

In order to modify a MRSA population and in turn, have the population able to propagate the modification, a method of delivery is essential. Conjugation, the horizontal transfer of genetic material between bacterial cells, is the proposed method for this delivery.

We decided to use conjugation as our mode of delivery because it has a large carrying capacity. Our silencing systems are quite large and therefore need the appropriate delivery mechanism. While a Staphylococcus virus would be more efficient at transferring DNA to a recipient cell, there are no Staphylococcus viruses that have been found with a carrying capacity large enough to handle our silencing systems. Conjugation is a transfer of genetic material between prokaryotes by cell-to-cell contact. This process is well characterized in gram-negative bacteria, such as E. coli, but it is less characterized in gram-positive bacteria like Staphylococcus aureus. To infer information on the gram-positive process, microbiologists usually use the gram-negative process as a template (Grohmann et al, 2003). The conjugation process in both gram-positive and gram-negative bacteria all share underlying similarities. For example, an origin of transfer (oriT) is required for all plasmid conjugation. A multiprotein complex that binds to the origin of transfer is called the relaxosome. The proteins involved in the relaxosome are coded within a tra/trs region that can be found on the plasmid or on the chromosome. The relaxosome is recognized by DNA relaxes which are able to perform a single or double stranded cut (depending on the type of system). The DNA released from the cut is then available to transfer to the recipient cells (Grohmann et al, 2003).

Design

Tab 2

content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2
content 2