QB3-UCSC Graduate Fellowship for Innovators
Plasmids are self-replicating pieces of DNA that play a key role in microbial ecology. Small, multicopy plasmids persist in bacterial populations despite being dispensable, imposing fitness costs on their hosts, and often lacking specialized mechanisms to ensure their stability. Our laboratory (and others) have recently established that these plasmids segregate non-randomly during cell division, yet the mechanisms regulating plasmid stability remain unknown. My research aims to identify these mechanisms using ColE1 plasmids as a model multicopy plasmid, filling a critical gap in our understanding of plasmid biology. Additionally, ColE1 plasmids are widely used as vectors for recombinant DNA expression due to their small size and high copy number. However, ColE1-based expression vectors tend to be unstable to the point that stability is a major factor that limits yield. Thus, understanding the mechanisms underlying ColE1 stability also has direct applications for the optimization of recombinant gene expression vectors.