The National Biomedical Resource for Advanced Electron-Spin Resonance Technologies (ACERT) is an outgrowth of extensive experience in developing the methods of modern electron spin resonance (ESR, a.k.a. EPR-Electron Paramagnetic Resonance) by Prof. Jack H. Freed’s research group at Cornell University. The technologies upon which this Resource is based are in many respects unique in the world, and their development has proven necessary for our many successful studies on protein structure and conformational dynamics conducted with numerous collaborators.

ACERT was originally a P41 NIH funded Center, which was heavily dedicated to ESR Technology, Research and Development (TR&D). The new R24 Resource is primarily dedicated to Collaborations and Service (C&S) in ESR. Even though the P41 Center was heavily involved in TR&D, C&S were an important component. For example the C&S projects on distance measurements (i.e. pulse dipolar spectroscopy, PDS) led to 10,000 PDS samples being studied and to 49 of the nearly 200 papers published by ACERT-P41, including its acknowledgements.

We expect that with the primary emphasis on C&S in the new R24 Resource, these activities will be significantly increased.

Our services to the ESR user community include:

• providing resources to the biomedical community,
• providing training in their use,
• publishing results,
• running workshops on these methodologies,
• addressing the need to bring these technologies to other laboratories.

Technologies

ESR characterization of proteins is of great importance in the better understanding of many diseases, including AIDS, allergies and inflammations, ALS, Alzheimer's, bacterial infection, cancer, cardiac disease, depressive disorders and schizophrenia, Ebola viral infections, eye disorders, infertility, neurological disorders, Parkinson's, and SARS-1/SARS-2. We have developed several different technologies to support such studies:

1) Pulsed Fourier Transform and Two Dimensional ESR from 9 to 35 GHz

• Distance Measurements in Proteins and Aggregates using Double Quantum Coherence ESR (DQC) and Double Electron-Electron Resonance (DEER);
• Dynamic Structure of Membranes and Proteins by 2D-ELDOR;
• Functional Dynamics of Proteins by Time Resolved FT and 2D-ESR;

2) ESR with Ultra-High Sensitivity for Very Small Biological Samples

3) High Frequency-High Field (HFHF) ESR

• 95-240 GHz ESR;
• Multifrequency Studies of Dynamics in Proteins and Membranes.
• 95 GHz 2D-ELDOR of Protein Dynamics
• 240 GHz composite pulse ESR
• Metallorganic Proteins in low temperature solids

4) Theory and Computational Methods for Modern ESR and Spectral Processing

• Signal processing to recover strong signals from weak ones.
• SVD (Singular Value Decomposition) to Determine Distance Distributions.
• Improved Theoretical and Computational Methods for Analyzing Modern ESR Experiments.

5) Conventional ESR cw and pulse experiments at 9-35 GHz.