Publications

Carcino-embryonic antigen-like cellular adhesion molecules (CEACAMs), members of the immunoglobulin superfamily, are responsible for cell-cell interactions and cellular signaling events. Extracellular interactions with CEACAMs have the potential to induce phagocytosis, as is the case with pathogenic Neisseria bacteria. Pathogenic Neisseria species express opacity-associated (Opa) proteins, which interact with a subset of CEACAMs on human cells, and initiate the engulfment of the bacterium. We demonstrate that recombinant Opa proteins reconstituted into liposomes retain the ability to recognize and interact with CEACAMs in vitro but do not maintain receptor specificity compared to that of Opa proteins natively expressed by Neisseria gonorrhoeae. We report that two Opa proteins interact with CEACAMs with nanomolar affinity, and we hypothesize that this high affinity is necessary to compete with the native CEACAM homo- and heterotypic interactions in the host. Understanding the mechanisms of Opa protein-receptor recognition and engulfment enhances our understanding of Neisserial pathogenesis. Additionally, these mechanisms provide insight into how human cells that are typically nonphagocytic can utilize CEACAM receptors to internalize exogenous matter, with implications for the targeted delivery of therapeutics and development of imaging agents.

Neisserial Opa protein-CEACAM interactions: Competition for receptors as a means of bacterial invasion and pathogenesis.
Martin JN, Ball LM, Solomon TL, Dewald AH, Criss AK, Columbus L.
Biochemistry. 55:4286-94 (2016).

Archive for

Shu X, Keller TC 4th, Begandt D, Butcher JT, Biwer L, Keller AS, Columbus L, Isakson BE.Endothelial nitric oxide synthase in the microcirculation
Cellular and Molecular Life Sciences 72:4561-75 (2015).

Archive for

Johnson MB, Ball LM, Daily KP, Martin JN, Columbus L and Criss AK. Opa+ Neisseria gonorrhoeae has reduced survival in human neutrophils via Src family kinase-mediated bacterial trafficking into mature phagolysosomes Cellular Microbiology.17:648-665 (2015)

Gray C, Price CW, Lee CT, Dewald AH, Cline MA, McAnany CE, Columbus L, Mura C. Known structure, unknown function: An inquiry-based undergraduate biochemistry laboratory course Biochemistry and Molecular Biology Education . 43: 245 – 262 (2015).

Archive for

Columbus L. Post-expression strategies for structural investigations of membrane proteins. Current Opinion in Structural Biology 32: 131 – 138 (2015).

Archive for

Columbus L, Kroncke B.Solution NMR Structure Determination of Polytopic α-Helical Membrane Proteins: A Guide to Spin Label Paramagnetic Relaxation Enhancement Restraints. Methods in Enzymology 557: 329 – 348 (2015).

Straub AC, Mutchler S, Billaud M, Mykhaylo A, Palmer L, Le TH, Somlyo AV, Columbus L, Isakson BE. Hemoglobin α/eNOS coupling in endothelium is required for nitric oxide scavenging during vasoconstriction. Arteriosclerosis, Thrombosis, and Vascular Biology 34:2594 – 2600 (2014).

Oliver RC, Lipfert J, Fox DA, Lo RH, Kim JJ, Doniach S, Columbus L. Tuning micelle dimensions and properties with binary surfactant mixtures
Langmuir. 30(44):13353-61 (2014)

Fox DA , Larsson P, Lo RH, Kroncke BM, Kasson PM, and Columbus L

Structure of the Neisserial Outer Membrane Protein Opa60: Loop Flexibility Essential to Receptor Recognition and Bacterial Engulfment. Journal of the American Chemical Society. 136:9938 – 9946 (2014).

And highlighted in JACS Spotlight.

Lo RH, Kroncke BM, Solomon TL, and Columbus L. Mapping Membrane Protein Backbone Dynamics: A Comparison of Site-Directed Spin Labeling with NMR 15N-Relaxation Measurements
Biophysical Journal. 107: 1697-702 (2014).

Butcher JT, Johnson T, Beers J, Columbus L, Isakson BE.Hemoglobin α in the blood vessel wall.Free Radical Biology & Medicine 73C:136 – 142 (2014).

Baker LA, Chakraverty D, Columbus L, Feig AL, Jenks WS, Pilarz M, Stains M, Waterman R, and Wesemann J. Cottrell Scholars Collaborative New Faculty Workshop: Professional Development for New Chemistry Faculty and Initial Assessment of Its Efficacy Journal of Chemical Education 91: 1874-1881 (2014).

Archive for

Fox DA and Columbus L. Solution NMR resonance assignment strategies for β-barrel membrane proteins. Protein Science. 22: 1133–1140 (2013).

Archive for ,

Anton BP et al. The COMBREX project: design, methodology, and initial results. PLoS Biol. 11:e1001638 (2013).

Archive for

Li J, Liu Q, Xiao L, Haverstick DM, Dewald A, Columbus L, Kelly KA, Landers JP. A Label-free Method for Cell Counting in Crude Biological Samples via Paramagnetic Bead Aggregation. Analytical Chemistry. 85:11233 – 11239 (2013).

Archive for

Kenwood BM, Weaver JL, Bajwa A, Poon IK, Byrne FL, Murrow BA, Calderone JA, Huang L, Divakaruni AS, Tomisg JL Okabe K, Lo RH, Coleman GC, Columbus L, Yan Z, Saucrman JJ, Smith JS, Homes JW, Lynch KR, Ravichandran KS, Uchiyama S, Santos WL, Rogers GW, Okusa MD, Bayliss DA, Hoehn KL. Identification of a novel mitochondrial uncoupler that does not depolarize the plasma membrane. Molecular Metabolism. 3:114 – 123 (2014).

Archive for ,

Oliver RC, Lipfert J, Fox DA, Lo RH, Doniach S, Columbus L. Dependence of Micelle Size and Shape on Detergent Alkyl Chain Length and Head Group PLoS ONE. 8:e62488 (2013).

Elkin SR, Kumar A, Price CW, Columbus L. A broad specificity nucleoside kinase from Thermoplasma acidophilum. Proteins. 81:568-82 (2013).

Straub AC, Lohman AW, Billaud M, Johnstone SR, Dwyer ST, Lee MY, Bortz PS, Best AK, Columbus L, Gaston B, Isakson BE. Endothelial cell expression of haemoglobin α regulates nitric oxide signalling. Nature. 491:473-7 (2012).

Kroncke BM, Columbus L. Backbone (1)H, (13)C and (15)N resonance assignments of the α-helical membrane protein TM0026 from Thermotoga maritima. Biomol NMR Assign. (2012).

Archive for

Johnstone SR, Kroncke BM, Straub AC, Best AK, Dunn CA, Mitchell LA, Peskova Y, Nakamoto RK, Koval M, Lo CW, Lampe PD, Columbus L, Isakson BE. MAPK phosphorylation of connexin 43 promotes binding of cyclin E and smooth muscle cell proliferation. Circulation Research 111:201-211 (2012).

Kroncke B.M. and Columbus L. Identification and removal of nitroxide spin label contaminant: Impact on PRE studies of α-helical membrane proteins in detergent. Protein Science 21: 589–595 (2012).

Dewald AH, Hodges JC, Columbus L. Physical Determinants of β-Barrel Membrane Protein Folding in Lipid Vesicles. Biophysical Journal 100:2131 – 2140 (2011).

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)

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).

Archive for

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)

Archive for

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).

Archive for

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)

Archive for

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)

Archive for

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)

Archive for

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)

Archive for

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)

Archive for

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)

Archive for

Columbus L, Hubbell WL. A new spin on protein dynamics. Trends in Biochemical Sciences, 27: 288-295 (2002)

Archive for

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)

Archive for

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)

Archive for

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)

Archive for