Eric WalterSenior Research Scientist, WR Wiley Environmental Molecular Sciences Laboratory, NMR & EPR
http://emslbios.pnl.gov/id/walter_ed Updated: February 20, 2012
Current Activities and Projects
Dr. Walter is the user contact for Electron Paramagnetic Resonance (EPR). He assists EMSL users in applying both X-Band and W-Band pulsed EPR spectroscopy to diverse fields, such as geochemistry, catalysis, metalloproteins, and solid-state physics.
Affinity and Dynamics of Tethered Biomolecules
Dr. Walter has developed a unique, continuous flow technique for determining the affinity of biomolecules for ligands. By tethering the biomolecule to a solid-phase (usually chromatography media), a column the dimensions of a typical EPR sample can be created. When placed in the EPR spectrometer, a continuous flow of ligand can be passed over the sample and the binding monitored in real time. This technique currently is being adapted to catalytic materials and a gas mobile phase.
Structure and theory of the Photosystem II Oxygen Evolving Center (OEC)
In collaboration with Ping Yang, Andrew Lipton, and K.V. Lakshmi, Dr. Walter is investigating the structure of the OEC, using a combination of magnetic resonance spectroscopy, cryogenic NMR, high-field EPR, and theoretical structure prediction. The research also involves using the theoretical prediction of magnetic resonance parameters in conjunction with the structure of known model compounds to refine experimental results.
2004-2009, Post-doctoral researcher, University of California, Santa Cruz (UCSC)
Prion Protein and Copper
While a post-doctoral researcher at UCSC in the lab of Glenn Millhauser, Dr. Walter developed several techniques for investigations of metalloproteins. Using solid-phase peptide synthesis and EPR, he was able to show that the natively unstructured octarepeat region of the prion protein used a series of different binding modes for copper, depending on the copper-to-protein ratio. He then developed a competition method for determining the affinity of each of these binding modes for copper. These results showed that the prion protein actually binds copper with negative cooperativity, not the positive cooperativity that had been previously reported. These techniques have been expanded to other metals (zinc) and proteins (α-synuclein).
Ph.D., Chemistry, Montana State University, Bozeman, Montana, 2004
B.S., Chemistry, University of Delaware, Newark, Delaware, 1996