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Marjorie L. Longo

Associate Professor, Joe and Essie Smith Professor of Chemical Engineering, Materials Science and Engineering, Chemical Engineering, University of California, Davis

IRG 2

Telephone: (530) 754-6348,
Fax: (530) 752-1031
Email: mllongo@ucdavis.edu

Associate Professor, Joe and Essie Smith Professor of Chemical Engineering, NSF Career Award, Department of Chemical Engineering and Materials Science, University of California, Davis, CA; B. A. 1988, Biochemistry-Molecular Biology, University of California, Santa Barbara, CA; Ph.D. 1993, Chemical Engineering, University of California, Santa Barbara, CA; NIH NRSA Postdoctoral Fellow, 1993-1996, Cornell University. Phone: (530) 754-6348, Fax: (530) 752-1031, email mllongo@ucdavis.edu.

In the Longo laboratory, we study the mechanical, barrier, transport, and adsorptive properties of artificial and real cell membranes that lead to macroscopic behaviors of biological membranes. Examples of these behaviors include viral infection, fertilization, action of anesthetics, membrane transport, and drug delivery. The softness of biological interfaces present special experimental problems associated with the fact that the core membrane component, the lipid bilayer, is fluid under physiological conditions. Therefore, we use mild micromanipulation techniques in which the pressure on the membrane can be varied by as little as one millionth of an atmosphere for measuring membrane mechanical properties and adsorption of water soluble species. We softly image the surface of the lipid bilayer using atomic force microscopy and fluorescence microscopy to examine phenomena at a range of length scales from nanometers to micrometers. Finally, for properties that can’t be observed experimentally, we develop computer simulations.

Selected Publications:

  1. Blanchette, C. D., Lin, W-C, Ratto, T. V., Longo, M. L. "Galactosylceramide Domain Microstructure: Impact of Cholesterol and Nucleation and Growth Conditions", Biophysical Journal, 90, 4466-4478, 2006.
  2. Blanchette, C. D., Ratto, T. V., Longo, M. L.; "Model Cell Membrane Surfaces For Measuring Receptor-Ligand Interactions". Cellular Engineering: Micromechanics at the Biomolecular Interface, editor M. R. King, Elsevier Science, 195-211, 2006.
  3. Pu, G., Borden, M. L., Longo, M. L., "Collapse and Shedding Transitions in Binary Lipid Monolayers Coating Microbubbles", Langmuir, 22: 2993-2999, 2006.
  4. Kraft, M. L., Weber, P. K., Longo, M. L., Boxer, S. G., Hutcheon, I. D., "Phase Separation of Lipid Membranes Analyzed with High-Resolution Secondary-Ion Mass Spectrometry", Science, 313, 1948-1951, 2006.
  5. Talu, E., Lozano, M. M., Powell, R.L., Dayton, P., Longo, M.L., "Long-term Stability by Lipid Coating Monodisperse Microbubbles Formed by a Flow Focusing Device", Langmuir, 22 :9487-9490, 2006.
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    Glazer, M.I., Fidanza, J.A., McGall, G.H., Trulson, M.O., Forman, J.E., Frank, C.W.; “Kinetics of Oligonucleotide Hybridization to DNA Probe Arrays on High-Capacity Porous Silica Substrates,” Biophysical Journal, 93, 1661-1676, 2007.

     

    Stalgren, J.J.R., Botschkova, K., Ericsson, J.-C., Frank, C.W., Knoll, W., Satija, S., Toney, M.F.; “Enrichment of Deuterium Oxide at Hydrophilic Interfaces in Aqueous Solutions,” Langmuir, 23, 11943-11946, 2007.

     

    Shen, Y., Powell, R. L., Longo, M. L.; “Interfacial and Stability Study of Microbubbles Coated with a Monostearin/Monopalmitin-Rich Food Emulsifier and PEG40 Stearate”, Journal of Colloid and Interface Science, 321, 186–194, 2008.

     

    Lee, J.S., Dylla-Spears, R., Teclemariam, N.P., Muller, S.J.; “Microfluidic Four-Roll Mill for all Flow Types”. Applied Physics Letters, 90, 074103, 2007.

    Kasson, P., Pande, V. S.; “Ensemble Molecular Dynamics Simulation Predicts Membrane Fusion Mechanism Controlled by Lipid Composition”. PloS Computational Biology, 3, 220, 2007

     

    Kasson. P., Zomorodian, A., Park, S., Singhal, N., Guibas, L., Pande, V. S.; “Persistent Voids: a New Structural Metric for Membrane Fusion”. Bioinformatics, 23, 1753-9, 2007.

     

    Lee, J.S., Shaqfeh, E.S.G., Muller, S.J.; “Dynamics of DNA Tumbling in Shear to Rotational Mixed Flows: Pathways and Periods”. Phys. Rev. E., 75, 040802(R), 2007.

     

    Teixeira, R., Dambal, A.K., Richter, D.H., Shaqfeh, E.S.G., Chu, S.; “The Individualistic Dynamics of Entangled DNA in Solution”. Macromolecules, 40, 7, 2461-2476, 2007.

     

  7. Tanaka, M., Hermann, J., Haase, I., Fischer, M., Boxer, S.; "Frictional Drag and Electrical Manipulation of Recombinant Proteins in Polymer Supported Membranes". Langmuir, 23, 5638-5644, 2007.

     

    Chan, Y.-H., Lenz, P., Boxer, S.; "Kinetics of DNA-Mediated Docking Reactions between Vesicles Tethered to Supported Lipid Bilayers". Proceedings of the National Academy of Sciences, 104, 18913-18918, 2007.

     

    ChanY.-H., Boxer,S. "Model Membrane Systems and their Applications". Current Opinion in Chemical Biology, 11, 581-587, 2007.

     

    Lin, W-C., Blanchette, C. D., Longo, M.L.; “Fluid-Phase Chain Unsaturation Controlling Domain Microstructure and Phase in Ternary Lipid Bilayers Containing GalCer and Cholesterol”. Biophysical Journal, 92, 2831-2841, 2007.

     

    Blanchette, C. D., Lin, W-C., Orme, C. A., Ratto, T. V., Longo, M. L., “Using Nucleation Rates to Determine Interfacial Line Tension of Symmetric and Asymmetric Lipid Bilayer Domains”. Langmuir, 23, 5875-5877, 2007.

     

    Blanchette, C. D., Orme, C. A., Ratto, T. V., Longo, M. L.; “Quantifying Growth of Symmetric and Asymmetric Lipid Bilayer Domains”. Molecular and Surface Forces, Langmuir Special Issue, 24, 1219-1224, 2008.

     

    Blanchette, C. D., Lin, W-C., Orme, C. A., Ratto, T. V, Longo, M. L., “Domain Nucleation Rates and Interfacial Line Tensions in Supported Bilayers of Ternary Mixtures Containing Galactosylceramide”. Biophysical Journal, 94, 2691–2697, 2008.

     

    Kasson, P., Pande, V. S.; “Predicting Structure and Dynamics of Loosely-Ordered Protein Complexes: Influenza Hemagglutinin Fusion Peptide.” Pacific Symposium on Biocomputing, 12, 40-50, 2007.

     

    Teclemariam, N.P., Beck, V.A., Shaqfeh, E.S.G., Muller, S.J.; “Dynamics of DNA Polymers in Post Arrays: Comparison of Single Molecule Experiments and Simulations”. Macromolecules, 40, 3848-3859, 2007.

    Lueth, C.A., Shaqfeh, E.S.G., “Tethered DNA Shear Dynamics in the Flow Gradient Plane: Application to Double Tethering”. Korea-Australia J. Rheol., 19, 3, 141-146, 2007.

     

    Beck, V.A., Shaqfeh, E.S.G., “Ergodicity-Breaking and the Unravelling Dynamics of a Polymer in Linear and Non-Linear Extensional Flows”. J. Rheol., 51, 3, 561-574, May/June, 2007.

     

    Hoffman, B., Shaqfeh, E.S.G., “The Dynamics of the Coil-Stretch Transition for Long, Flexible Polymers in Planar Mixed Flows''. J. Rheol., 51, 5, 947-969, 2007 (see also Virtual Journal of Biological Physics Research September 1, 2007.)

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