New Techniques In Single Molecule Optical Trapping: Passive Torque Wrench With A Single Beam Optical Trap And Dna Y Structure As A Versatile, Multidimensional Single Molecule Assay
Optical trapping is a powerful single molecule technique used to study dynamic biomolecular events, especially those involving DNA and DNA-binding proteins. The optical trap has the capability to stretch, twist, or unzip single DNA molecules, usually along a single dimension. Access to more dimensions of a single molecule system will be an essential feature in next generation single molecule tools to study more complex bimolecular systems, such as transcription and replication machinery, that stretch, twist, and unwind multiple strands of DNA. To this end, two new techniques for single molecule optical trapping are presented. First, a passive torque wrench is developed to increase the versatility and flexibility of the angular optical trapping technique by passively clamping the toque while simultaneously monitoring the angular orientation of the trapped particle. Second, a novel optical trapping assay is presented that allows simultaneous DNA stretching, twisting, unzipping, and fluorescence of a three-branch DNA construct, the DNA Y structure.
Optical trapping; Single molecule techniques; Angular optical trap
Wang, Michelle D
Vengalattore, Mukund; Sethna, James Patarasp
Ph. D., Physics
Doctor of Philosophy
dissertation or thesis