Research

Vibrational spectroscopy and conformational flexibility

My main research interest is the development of new physical techniques for understanding conformational flexibility and structural switching in proteins on a site-selected basis. The main instrumental techniques employed in my laboratory are infrared absorption spectroscopy and Raman scattering spectroscopy. We use the vibrational bands of native and modified amino acid side chains to determine the residue-level structural distribution of proteins with particularly dynamic structures.

Conformational flexibility is intrinsic to a protein’s ability to function; if proteins were not floppy, they couldn’t do anything! For enzymes, limited flexibility allows them to capture, convert and release specific chemical targets. For proteins that are building blocks in larger structures, the ability of the building blocks to adopt multiple shapes can allow the construction of complex biomolecular assemblies. For proteins involved in signalling and regulation, structural flexibility allows them to bind to many different targets in different ways. Vibrational spectroscopy is uniquely suited to observation of structural distributions, rather than just average protein structures. The techniques developed in my laboratory are being applied to understand the relationship between molecular flexibility and binding or self-assembly behavior in complexes made from multiple proteins: for example, viral capsids and multimeric enzymes.

Publications (*=undergraduates):

• Maienschein-Cline, Mark C.,* Londergan, Casey H. The CN stretching mode of aliphatic thiocyanate is sensitive to solvent dynamics and specific solvation. J. Phys. Chem. A 2007, 111, 10020-10025.

External funding:

• New Faculty Start-Up Award from the Camille and Henry Dreyfus Foundation, 2006-2011.