College of Science Graduate Program Profile: Professor Mark Williams
In my lab we study individual biological molecules such as DNA and proteins to try to understand how they work and what drives their interactions with each other. For example, we have instruments called optical tweezers that allow us to capture a single DNA molecule in between two polystyrene beads. We then use the tweezers to stretch the DNA, which can convert it from the double-stranded helical form (the form that stores our genetic information) to the single-stranded state, a state that is used by our cells to read and copy our genetic information. One new project we are working on is using this method to watch as single molecular motors called polymerases move along our captured single DNA molecule and add bases to one DNA strand using the information on the opposite strand in a process called DNA replication.