Single Molecule Studies of Motor Enzymes in Viral and Cellular DNA Packaging
Bacteriophages are viruses that infect bacteria. In the assembly of many phages a hollow protein capsid assembles first and is then filled with DNA by the action of a tiny "molecular motor" which is powered by chemical energy (ATP hydrolysis). We use optical tweezers to pull on a single DNA molecule as it is being packaged into a single phage capsid. This allows us to measure DNA translocation and the forces generated by the molecular motor in real time.