Michael F Brown

Michael F Brown

Professor, Chemistry and Biochemistry-Sci
Professor, Applied Mathematics - GIDP
Professor, BIO5 Institute
Member of the General Faculty
Member of the Graduate Faculty
Primary Department
Department Affiliations
Contact
(520) 621-2163

Research Interest

Michael F. Brown is Professor of Chemistry & Biochemistry at the University of Arizona. He is co-director of the Biological Physics Program and the Chemical Physics Program, and was a co-founder of the Biological Chemistry Program at the University of Arizona. He is internationally renowned for his work on the molecular basis of activation of G-protein-coupled receptors that are the targets for the majority of pharmaceuticals and medicines used by humans. The focus of his work is on biomembranes, with a particular emphasis on lipid-protein interactions in relation to potential drug targets involving membrane proteins. He is involved with investigation of the molecular basis of visual signaling involving rhodopsin. Moreover, Professor Brown is an expert in nuclear magnetic resonance (NMR) spectroscopy. His activities in the area of biomolecular NMR spectroscopy involve the devolvement and application of methods for studying the structure and dynamics of biomolecules. Michael Brown has authored over 130 original research papers, 10 book chapters, 4 book reviews, and has published more than 275 abstracts. His current H-index is 43. He numbers among his coworkers various prominent scientists worldwide. He presents his work frequently at national and international conferences, and is the recipient of a number of major awards. Professor Brown's many contributions have established him as a major voice in the area of biomembrane research and biomolecular spectroscopy. He is frequently a member of various review panels and exerts an influence on science policy at the national level. Among his accolades, he is an elected Fellow of the American Association for the Advancement of Science; American Physical Society; Japan Society for the Promotion of Science; and the Biophysical Society. He is a Fellow of the Galileo Circle of the University of Arizona. Most recently, he received the Avanti Award of the Biophysical Society. This premier honor recognizes his vast and innovative contributions to the field of membrane biophysics, and groundbreaking work in the development of NMR techniques to characterize lipid structure and dynamics. Most recently he presented the 2014 Avanti lecture of the Biophysical Society.

Publications

Struts, A. V., Barmasov, A. V., & Brown, M. F. (2016). Spectral Methods for Study of the G-Protein-Coupled Receptor Rhodopsin. II. Magnetic Resonance Spectroscopy. Optics and Spectroscopy, 118, 711-717.
Thurmond, R. L., Lindblom, G., & Brown, M. F. (1990). Influences of membrane curvature in lipid hexagonal phases studied by deuterium NMR spectroscopy. Biochemical and Biophysical Research Communications, 173(3), 1231-1238.

PMID: 2268326;Abstract:

The presence of reversed hexagonal phase, HII, favoring lipids in membranes has been proposed to be significant in various biological processes. Therefore an understanding of the HII phase and the transition from the lamellar to hexagonal phase is of importance. We have applied deuterium NMR spectroscopy to study the bilayer and reversed hexagonal phases of 1-perdeuteriopalmitoyl-2-linoleoyl-sn-glycero-3-phosphoethanolamine. The difference in packing between the HII and Lα phases leads to smaller segmental order parameters in the former case. Since the order profiles are sensitive to the geometry of the aggregates, they can be used to extract structural information about the phases. We present a new means of calculating the radius of curvature, R1, for the HII phase from 2H NMR data. This method gives a value of R1 = 18.1 Å, which is in agreement with current understanding of the structure of the HII phase and with x-ray diffraction data. © 1990 Academic Press, Inc.

Nevzorov, A. A., Trouard, T. P., & Brown, M. F. (1998). Lipid Bilayer Dynamics from Simultaneous Analysis of Orientation and Frequency Dependence of Deuterium Spin-Lattice and Quadrupolar Order Relaxation. Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 58, 2259-2281.
Leioatts, N., Mertz, B., Martínez-Mayorga, K., Romo, T. D., Pitman, M. C., Feller, S. E., Grossfield, A., & Brown, M. F. (2014). Retinal ligand mobility explains internal hydration and reconciles active rhodopsin structures. Biochemistry, 53(2), 376-385.

Abstract:

Rhodopsin, the mammalian dim-light receptor, is one of the best-characterized G-protein-coupled receptors, a pharmaceutically important class of membrane proteins that has garnered a great deal of attention because of the recent availability of structural information. Yet the mechanism of rhodopsin activation is not fully understood. Here, we use microsecond-scale all-atom molecular dynamics simulations, validated by solid-state 2H nuclear magnetic resonance spectroscopy, to understand the transition between the dark and metarhodopsin I (Meta I) states. Our analysis of these simulations reveals striking differences in ligand flexibility between the two states. Retinal is much more dynamic in Meta I, adopting an elongated conformation similar to that seen in the recent activelike crystal structures. Surprisingly, this elongation corresponds to both a dramatic influx of bulk water into the hydrophobic core of the protein and a concerted transition in the highly conserved Trp2656.48 residue. In addition, enhanced ligand flexibility upon light activation provides an explanation for the different retinal orientations observed in X-ray crystal structures of active rhodopsin. © 2013 American Chemical Society.

Chawla, U., Mertz, B., Ritter, E., Bartl, F., & Brown, M. F. (2014). Investigation of Lipid Bilayer Effects on Rhodopsin Activation using UV-Visible and FTIR Spectroscopy. Biophysical Journal, 106, 715a.