Conferences - Seminars

22OCT
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  Monday 22 October 2018 12:15 SV 1717

Chiral Sum Frequency Generation Spectroscopy for Protein Characterization at Interfaces

By Prof. Elsa C. Yan, Yale University, New Haven, CT (USA)

DISTINGUISHED LECTURE IN BIOLOGICAL ENGINEERING
(sandwiches served)

Abstract:
Characterization of protein secondary structures at interfaces in situ and in real time is important to understand biological processes associated with cell membranes and solve problems in various fields of biomedical sciences. However, such characterization is challenging because it requires methods that are both selective to interfaces and protein secondary structures. We demonstrate that chiral sum frequency generation spectroscopy (SFG) can provide peptide amide I and N-H stretch vibrational signals that are free of water background and characteristic to parallel beta-sheet, anti-parallel beta-sheet, alpha-helix, 3-10 helix and disordered structures, enabling chiral SFG to distinguish protein secondary structures at interfaces, similar to circular dichroism spectroscopy for protein characterization in solution. Using chiral SFG, we monitored misfolding of an amyloid protein, characterized protein orientation at interfaces, developed new methods for probing proton exchange in proteins, and studied two-dimensional crowding effects on protein folding at interfaces. These studies demonstrate chiral SFG as a new spectroscopic tool for characterizing protein structures and functions at interfaces, which can be used to address a wide range of fundamental and engineering problems.
 
Bio:
Elsa Yan was born and grew up in Hong Kong. She graduated from the Chinese University of Hong Kong in 1995. Working with Kenneth Eisenthal on nonlinear optics and surface sciences, she obtained her Ph.D. at Columbia University in 2000. From 2000-2004, she was a postdoctoral fellow in Richard Mathies's lab at UC Berkeley and a visiting fellow in Thomas Sakmar's lab at the Rockefeller University. She combined Raman spectroscopy with techniques in molecular biology to understand the molecular mechanism of signal transduction in the G-protein coupled receptor rhodopsin. In 2004, she joined The Rockefeller University, where she continued to develop methods in expression and purification of membrane proteins. In 2007, Elsa became an Assistant Professor of Chemistry at Yale. She was promoted to Associate Professor of Chemistry in 2012.

Organization Prof. Sylvie Roke

Contact Institute of Bioengineering (IBI, Christina Mattsson)

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Admittance Free