Our group studies the process of homologous recombination.  We focus on the DNA motor protein complexes or DNA nano-machines responsible for driving this process. These machines are frequently coupled to, or powered by, DNA helicases.  DNA helicases are ubiquitous enzymes whose primary function is to unwind DNA duplexes into their component single strands, a process that is coupled to the hydrolysis of nucleoside 5'-triposphates.  Our work is aimed at understanding the biochemical mechanism of DNA helicases and how these mechanisms contribute to and are adapted to the processes of recombination and DNA repair.

To see how DNA nano-machines put it all together, we use state-of-the-art single molecule techniques to visualize in real time, the dynamic properties of DNA nan-machines that are lost in the averaging process using conventional ensemble assays.  Single molecule manipulation and observation techniques provide an unparalleled and dramatic means to study biological reactions.  The two techniques we use are optical tweezers combined with video-fluorescence microscopy and atomic force microscopy.