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National Biomedical Center
for Advanced Electron Spin Resonance Technology

Our research is supported by a grant from the National Institute of General Medical Sciences (NIGMS), part of the National Institutes of Health.

Highlights of Core R & D at ACERT
ACERT's Collaborative Projects

Key Features of an Hsp70 Chaperone Allosteric Landscape Revealed by Double Electron-Electron Resonance and Ion Mobility Native Mass Spectrometry
Alex Liqi Lai, Eugenia M. Clerico, Mandy E. Blackburn, Nisha A. Patel, Carol V. Robinson, Peter P. Borbat, Jack H. Freed, and Lila M. Gierasch (June 2017)

Class II Viral Fusogens and the Ancestral Gamete Fusion Protein HAP2 are Linked using ESR Methodology
Jennifer Fricke Pinello, Alex Liqi Lai, Jean K. Millet, Donna Cassidy-Hanley, Jack H. Freed, and Theodore G. Clark (June 2017)

Signature of an Aggregation-Prone Conformation of Tau Elucidated by Pulse Dipolar ESR
Neil Eschmann, Elka R. Georgieva, Pritam Ganguly, Peter P Borbat, Maxime D. Rappaport, Yasar Akdogan, Jack H. Freed, Joan-Emma Shea, and Songi Han (June 2017)

Analysis of Protein Dynamics in the Solid-State from Lineshape Analysis of 2H NMR with Magic Angle Spinning
Eva Meirovitch, Zhichun Liang, and Jack H. Freed (June 2017)

Pulse Dipolar ESR Elucidates Conformational Response of Influenza A M2 Transmembrane Domain to Amantadine Drug Binding
E.R. Georgieva, P.P. Borbat, H.D. Norman, K. Grushin, S. Stoilova-McPhie, N.J. Kulkarni, Z. Liang, and J.H. Freed (June 2016)

Structural Basis for Activation, Assembly and Membrane Binding of ESCRT-III Snf7 Filaments Elucidated by Pulse Dipolar ESR
S. Tang, W.M. Henne, P.P. Borbat, N.J. Buchkovich, J.H. Freed, Y. Mao, J.C. Fromme, and S.D. Emr (June 2016)

Interaction of Spin-Labeled Lipid Membranes with Transition Metal Ions By Spin-Relaxation Enhancement
B. Dzikovski, V. Livshits, and J.H. Freed (June 2016)

Signal Transduction in Light-Oxygen-Voltage Receptors as Shown by Pulse-Dipolar ESR
E.F. Yee, R.P. Diensthuber, A.T. Vaidya, P.P. Borbat, C. Engelhard, J.H. Freed, R. Bittl, A. Möglich, and B.R. Crane (June 2016)

Assembly States within the Bacterial Flagellar Switch Complex as Elucidated by Pulse Dipolar ESR
R. Sircar, P.P. Borbat, M.J. Lynch, J. Bhatnagar, M. Beyersdorf, C.J. Halkides, J.H. Freed, and B.R. Crane (June 2016)

Protein Dynamics in the Solid-State from 2H NMR Lineshape Analysis: a Consistent Perspective
Eva Meirovitch, Zhichun Liang, and Jack H. Freed (June 2015)

Analysis of the Role of Tyrosyl Radicals in the Allosteric Regulation of COX-2
Benjamin J. Orlando, Michael G. Malkowski, Elka R. Georgieva, Peter P. Borbat, and Jack H. Freed (June 2015)

Bacterial Chemoreceptor Dynamics As Revealed by Pulsed Dipolar and Continuous Wave ESR Spectroscopy
Dipanjan Samanta, Peter P. Borbat, Boris Dzikovski, Jack H. Freed, and Brian R. Crane (June 2015)

Assembly of influenza M2 transmembrane domain
Elka R. Georgieva, Peter P. Borbat, Jack H. Freed, and Haley D. Norman (June 2014)

95GHz Pulsed ESR Technical Developments
Curt R. Dunnam, John M. Franck, Boris Dzikovski, Siddarth Chandrasekaran, Jack H. Freed, Keith A. Earle, Sameh El Naggar, and Sabah M Mattar (June 2014)

Probing the Structure of Flagellar Switch Complex from Thermotoga Maritima with Pulse-Dipolar ESR Spectroscopy
Ria Sircar, Michael Lynch, Peter P. Borbat, Jack H. Freed, and Brian R. Crane (June 2014)

Tau binds to lipid membrane surfaces via short amphipathic helices located in its microtubule-binding repeats
Elka R. Georgieva, Shifeng Xiao, Peter P. Borbat, Jack H. Freed and David Eliezer (June 2014)

The Internal Dynamics of Mini c TAR DNA Probed by Electron Paramagnetic Resonance of Nitroxide Spin-Labels at the Lower Stem, the Loop, and the Bulge
Yan Sun, Ziwei Zhang, Vladimir M. Grigoryants, William K. Myers, Fei Liu, Keith A. Earle, Jack H. Freed, and Charles P. Scholes (June 2013)

Unraveling the HAMP Mechanism in Bacterial Chemotaxis by Pulse Dipolar ESR
Dipanjan Samanta, Michael V. Airola, Nattakan Sukomon, Peter P. Borbat, Jack H. Freed, and Brian R. Crane (June 2013)

Pulsed-dipolar ESR spectroscopy of Cu2+-containing metalloproteins
Gregory E. Merz, Peter P. Borbat, Jack H. Freed, and Brian R. Crane (June 2013)

Portal to Lipoxygenase Active Site Revealed by Paramagnetic Distance Geometry
Betty J. Gaffney, Miles D. Bradshaw, Stephen Frausto (Biological Science, Florida State University, Tallahassee FL)
Jack H. Freed and Peter Borbat (ACERT)
June 2012

Conformational States of Glutamate Transporters from High-Sensitivity Pulse Dipolar ESR
Elka R. Georgieva, Peter P. Borbat, Chris Ginter , Olga Boudker, and Jack H. Freed (June 2012)

Pulsed ESR dipolar spectroscopy for distance measurements in immobilized spin labeled proteins in liquid solution
Zhongyu Yang, Yangping Liu, Peter Borbat, Jay L. Zweier, Jack H. Freed and Wayne L. Hubbell (June 2012)

Detecting Gas-Phase Free Radicals in Mainstream Cigarette Smoke
Long-Xi Yu, Boris G. Dzikovski, and Jack H. Freed (June 2012)

Conformational Distributions and Hydrogen Bonding in Gel and Frozen Lipid Bilayers: A High Frequency Spin-Label ESR Study
Boris Dzikovski, Dmitriy Tipikin, and Jack H. Freed (June 2012)

Diphthamide biosynthesis requires a SAM-dependent [4Fe-4S]-containing enzyme
Yang Zhang, Xuling Zhu, Andrew Torelli, Michael Lee, Boris Dzikovski, Rachel M. Koralewski, Eileen Wang, Jack H. Freed, Carsten Krebs, Steven E. Ealick, and Hening Lin (July, 2010)

Enhanced Sub-micron Resolution ESR Microscopy Applied to Cancerous Mouse Leg Tissue
Chang S. Shin, Curt R. Dunnam, Peter P. Borbat, Boris Dzikovski, Gene Barth, Howard Halpern, Michael Shklyar, and Jack H. Freed (July, 2010)

Multifrequency Electron Spin Resonance Study of T4 Lysozyme Dynamics
Ziwei Zhang, Dmitriy S. Tipikin, Zhichun Liang, Jozef K. Moscicki, Keith A. Earle, Mark R. Fleissner, Wayne L. Hubbell, Jack H. Freed (July 2009)

Chemotactic Receptor Interactions with Histidine Kinase CheA and the Coupling Protein CheW revealed by Pulsed Dipolar ESR Spectroscopy
Jaya Bhatnagar, Abiola M. Pollard, Peter P. Borbat, Jack H. Freed, Alexandrine M. Bilwes, and Brian R. Crane (July 2009)

Scanned-probe detection of electron spin resonance from a nitroxide spin probe
Eric W. Moore, Sang Gap Lee, Steven A. Hickman, Sarah J. Wright, Lee E. Harrell, Peter P. Borbat, Jack H. Freed, and John A. Marohn (July 2009)

Molecular-scale force measurement in a coiled-coil peptide by electron spin resonance
Stefano V. Gullà, Gaurav Sharma, Constantinos Mavroidis, Peter Borbat, Jack H. Freed, Harischandra Ghimire, Gary A. Lorigan, Kaushal Rege, David E. Budil (July 2009)

Membrane-Bound Alpha-Synuclein Forms an Extended Helix: Long-Distance Pulsed ESR Measurements Using Vesicles, Bicelles, and Rod-Like Micelles
Elka R. Georgieva, Trudy F. Ramlall, Peter P. Borbat, Jack H. Freed, David Eliezer (July 2009)

A Scissor Mechanism for Stimulation of SNARE-Mediated Membrane Fusion by Cholesterol
Jiansong Tong, Peter P. Borbat, Jack H. Freed, Yeon-Kyun Shin (July 2009)

Conformational Motion of the ABC Transporter MsbA Induced by ATP Hydrolysis
Peter P. Borbat, Jack H. Freed, Kavitha Surendhran, Marco Bortolus, Ping Zou, Hassane S. Mchaourab (June 2008)

Electron spin resonance spectra of a spin labeled protein calculated from molecular dynamics simulations
D. Sezer, J. H. Freed, B. Roux (June 2008)

Using Markov models to simulate electron spin resonance spectra from molecular dynamics trajectories
D. Sezer, J. H. Freed, B. Roux (June 2008)

Rigid Body Refinement of Protein Complexes with Long-Range Distance Restraints from Pulsed Dipolar ESR
J. Bhatnagar, J.H. Freed, and B. R. Crane (June 2007)

Two-Dimensional ELDOR Using Full Sc- Fitting and Absorption Lineshapes
Y.-W. Chiang, J.H. Freed, A. J. Costa-Fihlo (June, 2007)

Human and Rat Monoamine Oxidases are Dimeric in the Mitochondrial Outer Membrane
A. K. Upadhaya, P.P Borbat, J. Wang, J.H. Freed, D. E. Edmondson (June, 2007)

Sensitivity Improvement of Broadband High Frequency ESR Spectrometer: Application to HIV-Protease
D.S. Tipikin, K.A. Earle, J.H. Freed, L. Galiano, G. Fanucci (June, 2007)

Inter-helix distances in lysophospholipid micelle-bound alpha-synuclein from pulsed ESR measurements
P. P. Borbat, J. H. Freed, Trudy F. Ramlall, and David Eliezer (June, 2006)

Protein Dynamics from NMR: The Slowly Relaxing Local Structure Model with Rhombic Local Potential
Eva Meirovitch, Antonino Polimeno, J. H. Freed (June, 2006)

Collective Fluctuations in Membrane Vesicles Studied by 2D-ELDOR
Barbara Fresch, Giorgio Moro, J. H. Freed (June, 2006)

Dynamics of Nitroxide Side-Chain in Spin-Labeled Proteins
Fabio Tombolato, Alberto Ferrarini, J. H. Freed (June, 2006)

Pulsed ESR Studies of Interaction Interfaces Between T. Maritima CheA and CheW
S.-Y. Park, B. R. Crane, P. P. Borbat, A. M. Bilwes, J. H. Freed (June, 2005)

ESR Method for Determining Tie-lines in Coexisting Membrane Phases
J. Zhao, J. Wu, G. W. Feigenson, Y. Shimoyama, Y.-W. Chiang, J. H. Freed (June, 2005)

Distance Distributions in Protein Folding as Studied by Pulsed ESR: Cytochrome C
Y.-W. Chiang, P. P. Borbat, J. H. Freed, V. Grigoryantz, C. P. Scholes (June, 2005)

Pulsed ESR Microscopy of Biodegradable Microspheres
Aharon Blank, Curt Dunnam, Peter Borbat, Jack H. Freed, Naraharisetti Pavan Kumar, and Chi-Hwa Wang (June, 2005)

2D-ELDOR Studies Show Phase Structure Changes in Plasma Membrane Vesicles From RBL Cells Upon Stimulation
Yun-Wei Chiang, Jack H. Freed, Barbara A. Baird, David Holowka, Antonio J. Costa-Filho (June, 2005)

ESR studies of alpha-synuclein topology
D. Eliezer, P. P. Borbat, J. H. Freed (June, 2005)

Protein Dynamics Using Multi-Frequency ESR: T4 Lysozyme
Z. Liang, Y. Lou, J. H. Freed, L. Columbus, and W. L. Hubbell (June, 2004)

Effect Of Cholesterol Enrichment On Endoplasmic Reticulum Membranes
F. Maxfield, L. Ciani, I. Tabas, J. H. Freed, M. Ge, (June, 2004)

Coexisting Domains In The Plasma Membranes Of Live Cells By ESR
M. J. Swamy, L. Ciani, D. Holowka, B. Baird, M. Ge, J. H. Freed (June, 2004)

ESR Structural Studies of Peptoid Helices by Double-Quantum-Coherence ESR: Short Distances
Fafarman, B. Yoo, K. Kirshenbaum, P.P. Borbat, J.H. Freed (June, 2004)

Measurement of Large Distances in Biomolecules Using Double-Quantum-Filtered Refocused Electron-Spin-Echoes
Peter P. Borbat, Jack H. Freed, Jared H. Davis, Samuel E. Butcher, (June, 2004)

Protein Structure Using Double-Quantum Coherence ESR: T4 Lysozyme
P. Borbat, J. Freed, H. Mchaourab (June, 2002)

New Methods for Analyzing Heteronuclear NMR Relaxation Data from Proteins
E. Meirovitch, Z.Liang, J. Freed, V. Tugarinov (June, 2002)

Single-crystal Rotation Studies in High-Field/High Frequency ESR
S. K. Misra, K. A. Earle, J. H. Freed (June, 2002)