Preface
For this topical issue on membrane protein dynamics, we selected 27 papers encompassing the myriad of ways that membrane proteins interact with lipid membranes in several important biological systems. The membrane proteins featured in these papers range from small antimicrobial peptides to membrane-anchored functional peptides and proteins, to integral membrane proteins and channels. The diversity of these proteins and the membranes they interact with require ad hoc sample preparations as well as an array of spectroscopic approaches. In addition to the variety of experimental approaches, the most salient aspects of this special issue are the versatility and creativity that the researchers have applied to characterize the structure and dynamics of these biomolecules and to correlate these features to the biological function. From a spectroscopic view point, two major NMR approaches are represented: solution and solid-state NMR. Solution NMR methods for membrane proteins are traditionally applied to membrane proteins reconstituted in detergent micelles. However, a new method reviewed here encapsulates membrane proteins in reverse micelles, improving the overall rotational correlation time with a substantial gain in sensitivity and resolution. On the other hand, solid-state NMR does not suffer as a result of the slow tumbling of the molecular complexes, and can be used either for randomly oriented samples or for magnetically or mechanically aligned lipid membranes. The papers reported in this issue show that irrespective of the approach used, information on the dynamics of these polypeptides can be correlated to their biological function.
Gianluigi Veglia
Gianluigi Veglia is an Associate Professor of Chemistry and Biochemistry at the University of Minnesota. He received his M.S. from the University of Rome, La Sapienza, with a thesis on the “Synthesis and NMR Characterization of New β-Carboline Derivatives” under the direction of Professors M.R. Del Giudice and M. Delfini. He received his Ph.D. in physical chemistry from the University of Rome, La Sapienza. His thesis focused on the study of “Macromolecular Interactions by NMR Spectroscopy” carried out in the laboratory of Professor M. Delfini. During this time, he also studied the dynamics of small peptides and molecules using molecular dynamics simulations in collaboration with Professor A. Di Nola. Veglia carried out his postdoctoral studies with Professor S. Opella in the Chemistry Department of the University of Pennsylvania, where he optimized solution NMR methods for the structure determination of membrane proteins. In 2000, he joined the Department of Chemistry at the University of Minnesota as an Assistant Professor, where he began his independent program on the structural and dynamic characterization of soluble and membrane-bound proteins responsible for muscle contractility. He was then promoted to Associate Professor with a joint appointment between the Department of Chemistry and the Department of Biochemistry, Molecular Biology & Biophysics. Dr. Veglia uses an interdisciplinary approach to study the structure, dynamics, and interactions of integral and peripheral membrane proteins. Specifically, he combines solution NMR, solid-state NMR, and computational methods into a hybrid approach to determine the high-resolution structures and dynamic movements of proteins in membranes. More details about Dr. Veglia’s research projects can be found at www.chem.umn.edu/groups/veglia/.
Professor Ayyalusamy Ramamoorthy obtained his Ph.D. in Chemistry in 1990 from the Indian Institute of Technology (Kanpur, India) working on the development of NQR spectroscopy. He subsequently moved to the Central Leather Research Institute (a national research laboratory in Madras/Chennai, India) as a Fellow Scientist to develop scalar coupling based NMR methods for structural studies using solution NMR spectroscopy. In 1992, he joined JEOL Ltd (Tokyo, Japan) as a Scientist in the laboratory of Professor Kuniaki Nagayama to develop recoupling techniques (including USEME and J-HOHAHA) for magic angle spinning NMR studies on biological solids. He then joined the Stanley Opella group (University of Pennsylvania, Philadelphia) in 1993 to further develop and apply solid-state NMR techniques (including PISEMA, PSEUDO and PISEMAMAT) for structural studies of membrane proteins. In 1996, he joined the University of Michigan in Ann Arbor where he currently holds a joint appointment as Professor in Biophysics and Department of Chemistry. His main research interests are on the development and applications of solid-state NMR spectroscopy to study the structure, dynamics and function of membrane protein complexes, amyloid peptides, antimicrobial peptides, nanomedicine, and bone. His recent research revealed atomic-level mechanisms of membrane permeation/disruption by antimicrobial peptides and amyloid peptides, and reported high-resolution structure of membrane proteins. More details about his current research can be found at www.umich.edu/~ramslab.
