Interrogating Single Molecules Using Force

DBH 1100

ChEMS Seminar

Featuring Gaurav Arya, Ph.D.

Assistant Professor

Department of NanoEngineering

University of California, San Diego



Abstract:



Dynamic single molecule force spectroscopy provides a powerful approach for probing the underlying energy landscape that governs how molecules fold into complex 3D architectures, bind to each other, and undergo conformational transitions. These sophisticated experiments operate by imposing gradually increasing forces on single molecules (or complexes) and recording their force-extension behavior until eventual rupture. An outstanding question in this field is how to recover the intrinsic energy landscape of the molecule from such force measurements. In this talk I will describe the development of new theoretical models for extracting the height and location of activation energy barriers and intrinsic transition rates from single-molecule force measurements [1,2]. The models go beyond the current state-of-the-art by accounting for both the finite stiffness of the pulling device and the non-linear stretching of the molecular handles often used for connecting the molecule of interest to the device. I will end the talk by discussing other biophysical problems currently being investigated in our laboratory, related to the computational modeling of the in vivo structure, function, and regulation of DNA, chromatin, and chromosomes.

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[1] Maitra and Arya, PRL, 104, 108301, 2010



[2] Maitra and Arya, PCCP, in press, 2010



About the Speaker:



Gaurav Arya, Ph.D., is an assistant professor in the NanoEngineering Department at UC San Diego. He obtained a bachelor's degree in chemical engineering from IIT Bombay in 1998, and a Ph.D. degree in chemical engineering from the University of Notre Dame in 2003. He held two brief postdoctoral positions at Princeton University and New York University prior to joining UCSD. His research interests are in the areas of statistical mechanics, molecular modeling and simulations, chromatin biophysics, single molecule force spectroscopy, RNA design, and colloidal and polymer physics.