FCCT Biochemistry Lab:Research:Plasmid Engineering

Plasmids are circular DNA molecules that can be found in the cytoplasm of a wide spectrum of bacteria and in nuclei of some fungi. Early in the history of genetic engineering they were picked up as basic tools for introduction of foreign DNA into host cells. Plasmids are often very stable genetic elements that act in concert, but somehow independent of other genetic elements in the cell.

We wish to better understand the unusual complexity of mechanisms that are required for plasmid replication and persistence in bacterial cells. This would allow us to engineer improved vectors for synthetic biology and biotechnology.

Cyanobacterial plasmids

Some cyanobacterial species and strains collected a range of plasmids in their cytoplasms. While it is generally believed that they complement to rather small genomes and add genes that host cells might use in extreme environments or when under stress, a number of small cryptic plasmids exist for which no obvious evolutional advantage could be envisioned. What keeps these plasmids in the cells for thousands of generations? Which regulatory molecules are needed for such stability? How is their copy number regulated? Which events take place at ori sites when plasmid replication initiates? These are some of the questions that have not been adequately answered so far. We look forward to contribute to a broader understanding of this topic.