Purdue University School of Chemical Engineering Graduate seminar series Dr. Shekhar Garde, Head Rensselaer Polytechnic Institute "Water at Interfaces of Physical and Biological Systems: A New Molecular Perspective" September 18, 2012 9:00-10:15 a.m. FRNY G140 Reception at 8:30 a.m. in Henson Atrium Abstract: Water-mediated interactions (e.g., hydrophobic interactions) govern a host of biological and colloidal self-assembly phenomena from protein folding, micelle and membrane formation, to molecular recognition. Macroscopically, hydrophobicity is often characterized by measuring a droplet contact angle on a surface. At the nanoscale, such measurements are not feasible, e.g., for surfaces of proteins or nanoparticles. Using theory and molecular simulations, we present a new perspective that connects the behavior of water (esp. density fluctuations) near nanoscale interfaces to their hydrophobicity/philicity. This new perspective provides a computational tool for characterizing the hydrophobicity patterns on protein surfaces, which are relevant for binding, recognition, and aggregation phenomena. Simulations also show how the properties of water at interfaces influence binding, folding, and dynamics of flexible molecules in interfacial environments. Our current understanding of the hydration of ions, osmolytes, and solution additives, when combined with this new perspective, provides insights into the role of water in multicomponent biological interactions. Bio: Dr. Shekhar Garde is the Elaine and Jack Parker Chaired Professor and Head of Rensselaer's Department of Chemical and Biological Engineering. He received BS (University of Bombay, 1992) and Ph.D. (U. Delaware, 1997) degrees in Chemical Engineering. He received the prestigious Director's post-doctoral fellowship at Los Alamos National Laboratory, where he performed research from 1997 to 1999. He joined Rensselaer as an Assistant Professor in 1999. He was promoted to Associate Professor in 2004 and to Full Professor in 2006. He was appointed Parker Chaired Professor in 2006 and as the Head of Chemical and Biological Engineering Department in 2007. His research focuses broadly on understanding the role of water in biological structure-function, and specifically on hydration and water-mediated interactions using statistical mechanical theory and molecular modeling and simulation tools. He has published ~80 peer-reviewed papers in leading scientific journals which have been cited over 3700 times. He has received several awards including the prestigious CAREER Award by the US National Science Foundation (2001), School of Engineering Research Award (2003), Rensselaer Early Career Award (2004), and most recently the 2011 Robert W. Vaughan Lecturership at California Institute of Technology. Under Garde's leadership, the Chemical Engineering department climbed in US News & World Report Rankings from 33 to 21. Garde has also enabled a number of CBE faculty to win prestigious Rensselaer and National Awards. Garde is also one of the leaders of the unique animation movie project called the "Molecularium", which aims to excite the next generation about the world of atoms and molecules. He has pioneered integration of large-scale molecular dynamics simulations into Disney-Pixar style animation world. He is an executive producer of the Molecularium I-MAX/3-D-IMAX movies - Molecules to the MAX, which are currently being distributed nationwide. In 2011 he was honored with the Explore~Imagine~Discover Award by the Children's Museum of Science and Technology, in the Capital District, NY.