University of Mississippi View Institution's Website 7 articles published in JoVE Bioengineering Probing Myosin Ensemble Mechanics in Actin Filament Bundles Using Optical Tweezers Omayma Al Azzam*1, Janie C. Watts*1, Justin E. Reynolds2, Juliana E. Davis2, Dana N. Reinemann1,2 1Department of Chemical Engineering, University of Mississippi, 2Department of Biomedical Engineering, University of Mississippi Formation of actomyosin bundles in vitro and measuring myosin ensemble force generation using optical tweezers is presented and discussed. Biochemistry Laser-free Hydroxyl Radical Protein Footprinting to Perform Higher Order Structural Analysis of Proteins Scot R. Weinberger1, Emily E. Chea1, Joshua S. Sharp1,2,3, Sandeep K. Misra2 1GenNext Technologies Inc., 2Department of Biomolecular Sciences, School of Pharmacy, University of Mississippi, 3Department of Chemistry and Biochemistry, University of Mississippi This protocol presents a method to use inline radical dosimetry and a plasma light source to perform flash oxidation protein footprinting. This method replaces the hazardous UV laser to simplify and improve the reproducibility of fast photochemical oxidation of protein studies. Biochemistry Enabling Real-Time Compensation in Fast Photochemical Oxidations of Proteins for the Determination of Protein Topography Changes Sandeep K. Misra1, Joshua S. Sharp1,2,3 1Department of Biomolecular Sciences, University of Mississippi, 2Department of Chemistry and Biochemistry, University of Mississippi, 3GenNext Technologies, Inc. Fast photochemical oxidation of proteins is an emerging technique for the structural characterization of proteins. Different solvent additives and ligands have varied hydroxyl radical scavenging properties. To compare the protein structure in different conditions, real-time compensation of hydroxyl radicals generated in the reaction is required to normalize reaction conditions. Biology A Cost Effective and Adaptable Scratch Migration Assay Stephanie D. Burr1, James A Stewart, Jr.1 1Department of BioMolecular Sciences, University of Mississippi We present a cost-effective method to the scratch migration assay that provides a new approach for determining cell migration without the use of equipment-intensive methods. While fibroblasts were used in this protocol, it can be adapted and utilized to study additional cell types and influences on cell migration. Bioengineering Preparation of Neutrally-charged, pH-responsive Polymeric Nanoparticles for Cytosolic siRNA Delivery John Hendershot1, Adam E. Smith1, Thomas A. Werfel1,2,3 1Department of Chemical Engineering, University of Mississippi, 2Department of BioMolecular Sciences, University of Mississippi, 3Biomedical Engineering Program, University of Mississippi Methods to prepare and characterize the physicochemical properties and bioactivity of neutrally-charged, pH-responsive siRNA nanoparticles are presented. Criteria for successful siRNA nanomedicines such as size, morphology, surface charge, siRNA loading, and gene silencing are discussed. Environment Determination of Microbial Extracellular Enzyme Activity in Waters, Soils, and Sediments using High Throughput Microplate Assays Colin R. Jackson1, Heather L. Tyler1, Justin J. Millar1 1Department of Biology, The University of Mississippi Microplate based procedures are described for the colorimetric or fluorometric analysis of extracellular enzyme activity. These procedures allow for the rapid assay of such activity in large numbers of environmental samples within a manageable time frame. Immunology and Infection A Parasite Rescue and Transformation Assay for Antileishmanial Screening Against Intracellular Leishmania donovani Amastigotes in THP1 Human Acute Monocytic Leukemia Cell Line Surendra K. Jain1, Rajnish Sahu1, Larry A. Walker1,2, Babu L. Tekwani1,2 1National Center for Natural Products Research, School of Pharmacy, University of Mississippi, 2Department of Pharmacology, University of Mississippi A parasite-rescue and transformation assay with THP1 cells infected in vitro with Leishmania donovani has been optimized for anti-leishmanial drug screening. The assay involves differentiation of THP1 cells, infection with promastigotes, treatment with test drugs, controlled lysis of the infected macrophages, rescue of amastigotes, transformation to promastigotes and monitoring promastigote growth and proliferation with a fluorometric assay.