Dewald AH, Hodges JC, Columbus L. Biophysical Journal 100:2131 – 2140.
The spontaneous folding of two Neisseria outer membrane proteins, opacity-associated (Opa)60 and Opa50 into lipid vesicles was investigated by systematically varying bulk and membrane properties. Centrifugal fractionation coupled with sodium dodecyl sulfate polyacrylamide gel electrophoresis mobility assays enabled the discrimination of aggregate, unfolded membrane-associated, and folded membrane-inserted protein states as well as the influence of pH, ionic strength, membrane surface potential, lipid saturation, and urea on each. Protein aggregation was reduced with increasing lipid chain length, basic pH, low salt, the incorporation of negatively charged guest lipids, or by the addition of urea to the folding reaction. Insertion from the membrane-associated form was improved in shorter chain lipids, with more basic pH and low ionic strength; it is hindered by unsaturated or ether-linked lipids. The isolation of the physical determinants of insertion suggests that the membrane surface and dipole potentials are driving forces for outer membrane protein insertion and folding into lipid bilayers.
Linda Columbus
PI
Postdoctoral Research: The Scripps Research Institute
Advisors: Kurt Wuthrich and Scott Lesley
NMR and X-ray crystallography of Membrane proteins.
PhD: The University of California Los Angeles (2001)
Advisor: Wayne Hubbell
Mapping protein backbone dynamics with EPR Spectroscopy and site – directed spin labeling.
BA, high honors: Smith College (1996)
Advisor: David Bickar
Professor Columbus is interested in accelerating membrane protein techniques to investigate the structure and dynamics of membrane proteins involved in bacterial pathogenesis.
Kroncke BM, Horanyi PS, and Columbus L. Structural origins of nitroxide side chain dynamics on membrane protein α-helical sites. Biochemistry 49:10045–10060 (2010)
Alison and Jackie’s paper #15 of the “Top 25 Hottest Articles” in Biophysical Journal
According to Science Direct, from April to June 2011
Physical Determinants of Beta-Barrel Membrane Protein Folding in Lipid Vesicles
Biophysical Journal, Volume 100, Issue 9, May 2011, Pages 2131-2140
Dewald, Alison H.; Hodges, Jacqueline C.; Columbus, L.
is 15th in the “Top 25 Hottest Articles” of Biophysical Journal.
Beuck C, Szymczyna BR, Kerkow DE, Carmel AB, Columbus L, Stanfield RL, Williamson JR. Structure of the GLD-1 homodimerization domain: insights into STAR protein-mediated translational regulation. Structure 18:377-89 (2010).
Columbus L, Lipfert J, Jambunathan K, Fox DA, Sim AYL, Doniach S, and Lesley SA. Mixing and Matching Detergents for Membrane Protein NMR Structure Determination J. Am. Chem. Soc. 131:7320–7326 (2009)
Columbus L, Nakamoto, RK, Cafiso, DS. Chapter in Wiley Encyclopedia of Chemical Biology (2008)
McCleverty C*, Columbus L*, Kreusch A, Lesley SA. Structure and ligand binding of the soluble domain of a Thermotoga maritima membrane protein of unknown function TM1634. Protein Science 17:869-77 (2008).
Lipfert J, Columbus L, Chu V, Doniach S. Analysis of small-angle X-ray scattering data of protein-detergent complexes with singular value decomposition. Journal of Applied Crystallography 40: s235-s239 (2007)
Dan and Linda contribute to CIL’s Biomolecular NMR Product Catalog.
The new Cambridge Isotope Laboratories, Inc. Biomolecular NMR Product Catalog has pieces written by various NMR spectroscopists that utilize their isotopes. Dan adn Linda wrote a piece entitled “The role of deuterated detergents in NMR structure determination of membrane proteins” and is found on page 33. 
Lipfert J, Columbus L, Chu V, Lesley SA, Doniach S. Size and shape of detergent micelles determined by small-angle X-ray scattering. Journal of Physical Chemistry B 111: 12427-12438 (2007)
Columbus L, Lipfert J, Klock H, Millet I, Doniach S, Lesley SA. Expression, purification, and characterization of Thermotoga maritimamembrane proteins for structure determination. Protein Science 15: 961-975 (2006)
Ryan, Ryan, and Linda attend the MidAtlantic BioSAXS Workshop
This April, Ryan Oliver, Ryan Lo, and Linda attended the Rigaku and UNC Chapel Hill sponsored MidAtlantic BioSAXS Workshop. The day-long workshop focused on the latest developments in BioSAXS technologies and applications.
Columbus L, Peti W, Herrmann T, Etezady T, Wüthrich K. NMR structure determination of the conserved hypothetical protein TM1816 from Thermotoga maritima . Proteins: Structure, Function and Bioinformatics 60: 552-557 (2005)
Columbus L, Hubbell WL. Mapping backbone dynamics in solution with site-directed spin labeling: GCN4-58 bZip free and bound to DNA. Biochemistry 43: 7273-7287 (2004)
Liang ZC, Lou Y, Freed JH, Columbus L, Hubbell WL. A multifrequency electron spin resonance study of T4 lysozyme dynamics using the slowly relaxing local structure model Journal of Physical Chemistry B 108: 17649-17659 (2004)
Columbus L, Hubbell WL. A new spin on protein dynamics. Trends in Biochemical Sciences, 27: 288-295 (2002)
Linda, Dan, and Brett attended Frontiers of NMR in Biology Keystone Symposium
Dan presented a poster entitled “NMR Backbone Assignment of Opa I: A mediator of host-Neisseria interactions” and Brett presented a poster entitled “Investigations towards improving solution NMR paramagnetic relaxation enhancement distance restraints for MTSSL labeled α-helical membrane proteins”. Both were invited to orally present poster previews and Dan received a travel award. The meeting was located in Big Sky, Montana and the snow was fantastic.
Columbus L, Kalai T, Jeko J, Hideg K, Hubbell WL. Molecular motion of spin labeled side chains in α-helices: Analysis by variation of side chain structure. Biochemistry 40: 3828-3846 (2001)
Linda receives a 2010 Cottrell Scholar Award
The Cottrell Scholar Award (awarded by the Research Corporation for Science Advancement) supports the Columbus lab’s research on the structure and dynamics of bacterial outer membrane proteins and their interactions with host receptors. Specifically, the proposal focuses on the outer membrane opacity-associated (Opa) proteins from Neisseria, which induce engulfment of the bacterium in non-phagocytic cells by binding to host receptors. The results may provide insight into the pathogenesis of Neisseria, aid in the rational design of novel antibiotics, vaccine development, and targeting of liposome pharmaceutical carriers. The education component of the award allows Prof. Columbus to offer a UVA chemistry undergraduate course, which will introduce methods of drug discovery, entitled “From Lab Bench to Your Medicine Cabinet” in Fall 2011.
The Cottrell Scholar Awards are designed for institutions and faculty members who are committed to excel at both teaching and research. These awards ($75,000) enable recipients to implement their plans to become outstanding scientists and educators as well as tomorrow’s academic and scientific leaders. The awards also seek to reinforce faculty mentoring, communication, and a heightened appreciation for instruction in university science departments. This year their were 11 recipients of the award including another UVA faculty, Prof. Austen Lamacraft, in the UVA Physics Department.
The Cottrell Scholar Awards, instituted in 1994, are named in honor of Frederick Gardner Cottrell, scientist, inventor, and philanthropist. Dr. Cottrell founded Research Corporation for Science Advancement in 1912 and provided means for scientific research and experimentation at scholarly institutions. He not only contributed fundamentally and practically to scientific knowledge, but he dedicated his career to enlisting science in the service of society.
Gaponenko V, Howarth JW, Columbus L, Gasmi-Seabrook G, Yuan J, Hubbell WL, Rosevear PR. Protein global fold determination using site-directed spin and isotope labeling. Protein Science 9: 302-309 (2000)
Gross A, Columbus L, Hideg K, Altenbach C, Hubbell WL. Structure of the KcsA potassium channel from Streptomyces lividans: A site-directed spin labeling study of the second transmembrane segment. Biochemistry 38: 10324-10335 (1999)
Alison presents poster at FASEB Summer Research Conference
Alison presented a poster entitled “Physical determinants of outer membrane Opacity-associated protein folding in lipid vesicles” this August at the Molecular Biophysics of Cellular Membranes FASEB Summer Research Conference.
Alison on a hike in the White Mountains of Vermont.
Alison and Linda on the same hike.
Columbus and Criss labs receive UVA nanoSTAR seed funds
UVA nanoSTAR Institute awarded $30,000 to the Columbus and Criss laboratories to facilitate a collaboration aimed at targeting liposomes cell specifically. The nanoSTAR seed projects fund is contributed to by the Office of the Vice President for Research, the College of Arts and Sciences, the School of Engineering and Applied Science, and the School of Medicine. The nanoSTAR Seed Fund program is designed to support promising new interdisciplinary research collaborations in the Institute’s three thrust areas: nanoelectronics, medicine, and energy and the environment.
Alison and Dan present at the Biophysical Society’s 54th Annual Meeting
Alison and Dan present at the Biophysical Society’s 54th Annual Meeting at the Moscone Convention Center in San Francisco, California, February 20-24, 2010. Dan presented a poster on the NMR structure determination of OpaI and Alison presented a talk on the molecular determinants of the spontaneous refolding of OpaI in lipid vesicles.
UVA Chemistry Colleague and Chair, David Cafiso, received a Fellow of the Biophysical Society award. 