Biochemistry, Biophysics, and Structural Biology Commons^™

Combating Bioterrorism: Purification And Structural Analysis Of The E3 Proteins Of The Venezuelan Equine Encephalitis Virus And The Chikungunya Virus, Tyshia Gwin

The Journal of Purdue Undergraduate Research

Outbreaks of the Venezuelan Equine Encephalitis Virus (VEEV) and the Chikungunya Virus (CHIKV) continue to emerge in Central and South America, Africa, and Asia, but there are currently no vaccines or anti-virals for these viruses. Given their ease of transmission, debilitating symptoms, and genetic alterability, VEEV and CHIKV have great potential for development into biological weapons. Therefore, there is an urgent need to determine possible methods of treatment or prevention. One possibility of prevention lies in determining the structure and biological function of the E3 protein that plays a key role in the infectivity of the viruses. In this research, …

Role Of Tyk2 In The Development Of Beige Cells, Samantha Umali

Theses and Dissertations

Obesity results from an excess of adipose tissue and is a major risk factor for type 2 diabetes, cardiovascular disease, and cancer. Adipose tissue exists in two main forms: white adipose tissue (WAT), which stores energy as triglycerides, and brown adipose tissue (BAT), which dissipates stored energy as heat. White adipose tissue is composed of several subcutaneous and visceral depots, each possessing distinct molecular and functional characteristics. Brown-like adipocytes can emerge in WAT depots in response to cold or beta-adrenergic stimulation. These cells have been called “beige” or “brite” (brown-in-white) cells. The reduction of obesity in mice treated with beta-adrenergic …

Regulation Of Cytosolic Phospholipase A2 (Cpla2) And Its Association With Cell Proliferation In Human Lens Epithelial Cells, Yin Wang, Kui-Yi Xing, Marjorie F. Lou

School of Veterinary and Biomedical Sciences: Faculty Publications

PURPOSE. To investigate the molecular mechanism for cytosolic phospholipase A2 (cPLA2) regulation and its association to platelet-derived growth factor (PDGF)-induced cell proliferation.

METHODS. cPLA2 was examined using human lens epithelial (HLE) B3 cells. Reactive oxygen species (ROS) generation induced by PDGF was analyzed by luminescence assay. Cell proliferation was measured by cell counting and by BrdU assay. Human cPLA2 gene was cloned via RT-PCR followed by sitedirected mutagenesis to construct HLE B3 cells expressing either inactive cPLA2 enzyme with S228A mutation (S228A), or cPLA2 truncated at the calcium-binding C2 domain (C2D). Activity of cPLA2 was measured by arachidonic acid (AA) …

Cloning, Expression, And Characterization Of The Aminoethylphosphonate Pathway In Trypanosoma Cruzi, Samuel I. Rodriguez^, Esteban M. Cordero, Igor C. Almeida*

COURI Symposium Abstracts, Summer 2011

No abstract provided.

Thermal-Initiated Hydroxyethyl Methacrylate Functionalization Of Multiwalled Carbon Nanotubes, Greg Curtzwiler, Philip Costanzo, Ray Fernando, Jeffrey E. Danes, Keith Vorst

Chemistry and Biochemistry

Multiwalled-carbon nanotubes (MWCNTs) were functionalized via thermoinitiated free radical polymerization of 2-hydroxyethyl methacrylate (HEMA) using benzoyl peroxide. Tip sonication was used during the polymerization reaction to separate agglomerated nanotubes. The functionalization was confirmed by control experiments and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Differential scanning calorimetry indicated that the addition of poly(HEMA)-MWCNTs to a two-component polyurethane coating will have little effect on the glass transition temperature of the coating. The poly(HEMA)-functionalized MWCNTs formed large colloidal structures of highly dispersed nanotubes in both the nonsheared and sheared coatings as determined by atomic force microscopy. This study determined a quick …

Characterization Of Lysophosphatidic Acid Subspecies Using A Novel Hplc Esi-Ms/Ms Method, Eric Mayton

Theses and Dissertations

Lysophosphatidic acid (LPA) is a bioactive lipid with a plethora of biological functions, including roles in cell survival, proliferation, and migration. Although high-performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC ESI-MS/MS) technology has been used to measure the levels of LPA in human blood, serum and plasma, current methods cannot readily detect the minute levels of LPA from cell culture. In this study, a novel HPLC ESI-MS/MS method with enhanced sensitivity was developed which allows accurate measurements of LPA levels with a limit of quantitation at approximately 10 femtomoles. The method was validated by quantitation of LPA levels in …

Emerging Dynamics Of Human Campylobacteriosis In Southern Ireland, Susan Bullman, Daniel Corcoran, James O'Leary, Derry O'Hare, Brigid Lucey, Roy D. Sleator

Department of Biological Sciences Publications

Infections with Campylobacter spp. pose a significant health burden worldwide. The significance of Campylobacter jejuni/Campylobacter coli infection is well appreciated but the contribution of non-C. jejuni/C. coli spp. to human gastroenteritis is largely unknown. In this study, we employed a two-tiered molecular study on 7194 patient faecal samples received by the Microbiology Department in Cork University Hospital during 2009. The first step, using EntericBio® (Serosep), a multiplex PCR system, detected Campylobacter to the genus level. The second step, utilizing Campylobacter species-specific PCR identified to the species level. A total of 340 samples were confirmed as Campylobacter genus positive, 329 of …

Structures Of Poliovirus And Antibody Complexes Reveal Movements Of The Capsid Protein Vp1 During Cell Entry, Jun Lin

Theses and Dissertations

In the infection process, native poliovirus (160S) first converts to a cell-entry intermediate (135S) particle, which causes the externalization of capsid proteins VP4 and the N-terminus of VP1 (residues 1-53). The externalization of these entities is followed by release of the RNA genome, leaving an empty (80S) particle. Three antibodies were utilized to track the location of VP1 residues in different states of poliovirus by cryogenic electron microscopy (cryo-EM). "P1" antibody binds to N-terminal residues 24-40 of VP1. Three-dimensional reconstruction of 135S-P1 showed that P1 binds to a prominent capsid peak known as the "propeller tip". In contrast, our initial …

The Molecular Mechanism Of Migraine, Kristin Dawn Watson

Theses and Dissertations

Migraine is a common, episodic neurological disorder that includes headache, nausea and hypersensitivity to sensory stimuli. During the headache phase of migraine, migraine patients can be especially hypersensitive to thermal stimuli. The unpredictable and episodic nature of migraine makes it difficult to treat and much of the mechanism of migraine has yet to be elucidated. A T44A substitution in casein kinase 1δ is inherited with migraine with aura. A transgenic mouse model suggests that animals with this mutation exhibit increased sensitivity to thermal stimuli after injection with nitroglycerin (NTG). We performed behavior assays that measure animal responses to thermal stimuli, …

The Occurrence Of False Positive Tests For Gunshot Residue Based On Simulations Of The Suspect's Occupation, Christopher R. Dockery, Matthew B. Rosenberg, Kimberly Kammerdiener, Lauren E. Mcadams

Faculty Articles

Samples collected from high-risk occupations, or simulations thereof, are analyzed for elemental composition using laser-induced breakdown spectroscopy (LlBS) to determine the occurrence of false positive gunshot residue results generated in the work environment. Previous work involving the study of lifetime of detectable amounts of gunshot residue on the hands of a suspect shooter found that gunshot residue exists up to 5.27 days after a firearm discharge. However, certain environmental and/or occupational false positive tests for gunshot residue could result when sampling non-shooters. Samples collected from occupations or simulations thereof include welding, pyrotechnics, key cutting, mechanics, and paper products all of …

Quantifying The Flux Of Caco3 And Organic Carbon From The Surface Ocean Using In Situ Measurements Of O-2, N-2, Pco(2), And Ph, Steven Emerson, Christopher Sabine, Meghan F. Cronin, Richard Feely, Sarah E. Cullison Gray, Michael Degrandpre

Chemistry and Biochemistry Faculty Publications

Ocean acidification from anthropogenic CO2 has focused our attention on the importance of understanding the rates and mechanisms of CaCO3 formation so that changes can be monitored and feedbacks predicted. We present a method for determining the rate of CaCO3 production using in situ measureme nts of fCO(2) and pH in surface waters of the eastern subarctic Pacific Ocean. These quantities were determined on a surface mooring every 3 h for a period of about 9 months in 2007 at Ocean Station Papa (50 degrees N, 145 degrees W). We use the data in a simple surface ocean, mass balance …

Novel Ion Trap Made Using Lithographically Patterned Plates, Ying Peng

Theses and Dissertations

A new approach of making ion trap mass analyzers was developed in which trapping fields are created in the space between two ceramic plates. Based on microfabrication technology, a series of independently-adjustable electrode rings is lithographically patterned on the facing surfaces of each ceramic plate. The trapping field can be modified or fine-tuned simply by changing the RF amplitude applied to each electrode ring. By adjusting the potential function applied to the plates, arbitrary trapping fields can be created using the same set of ceramic plates. Unlike conventional ion traps, the electrodes of planar ion traps have a non-equipotential surface, …

Sunday Driver/Jip3 Binds Kinesin Heavy Chain Directly And Enhances Its Motility, Faneng Sun, Chuanmei Zhu, Ram Dixit, Valeria Cavalli

Biology Faculty Research

Neuronal development, function and repair critically depend on axonal transport of vesicles and protein complexes, which is mediated in part by the molecular motor kinesin‐1. Adaptor proteins recruit kinesin‐1 to vesicles via direct association with kinesin heavy chain (KHC), the force‐generating component, or via the accessory light chain (KLC). Binding of adaptors to the motor is believed to engage the motor for microtubule‐based transport. We report that the adaptor protein Sunday Driver (syd, also known as JIP3 or JSAP1) interacts directly with KHC, in addition to and independently of its known interaction with KLC. Using an in vitro motility assay, …

Crosstalk Between Wnt And Rho Pathways In Ameloblast-Lineage Cells, Kate Shusterman

PCOM Biomedical Studies Student Scholarship

Exposure to high levels of fluoride during tooth development will lead to mineralization defects and a decrease in enamel strength, known as enamel fluorosis. It has been proposed that fluoride may alter the cytoskeleton of ameloblasts, cells that secrete enamel during tooth development. This change is carried out through the Rho pathway, more specifically through RhoA. RhoA is stimulated by Wnt3a, a part of the Wnt pathway involved in regulation of cell proliferation and differentiation. The main component of the Wnt pathway, β-catenin, is expressed in dental epithelium and acts by linking cadherins to the actin cytoskeleton in cell adhesion. …

The Mitospecific Region Of Mrp20 And Its Importance For The Assembly Of Mitochondrial Ribosomes In Saccharomyces Cerevisiae, Jasvinder Kaur

Dissertations (1934 -)

Yeast mitochondrial ribosomes are composed of an rRNA scaffold, encoded by the mitochondrial genome and many different proteins, which, with the exception of one, are encoded by nuclear genes. These ribosomal proteins are imported into the mitochondrial matrix following their synthesis in the cytosol, however, little is known about the subsequent events which result in an assembled, translationally-competent ribosome. Many of the mitochondrial ribosomal proteins bear homology to bacterial ancestors. In addition to the acquisition of mitochondrial targeting signals, a number of these nuclearly-encoded ribosomal proteins have acquired additional domains, often at their C-termini, which are termed "mitochondrial-specific domains". The …

Nanosecond Pulsed Electric Field Induction Of Programmed Cell Death Is Cell Type Dependent: An In Vitro Study, Wei Ren

Theses and Dissertations in Biomedical Sciences

Nanosecond pulsed electric fields (nsPEFs) present a novel and effective method for cancer ablation by eradicating the ubiquitous cancer hallmark of apoptosis evasion and enforcing cancer programmed cell death. To develop nsPEFs as an anticancer method, a comprehensive understanding of cell death mechanisms is required. The overall objective of this dissertation is to elucidate molecular mechanisms underlying effects of nsPEFs on E4 murine squamous cell carcinoma and human T-cell Jurkat clones that are wildtype, deficient in FADD (ΔFADD) and deficient in caspase-8 (ACas-8). The overall hypothesis is that nsPEFs eliminate cancer cells through activating caspase-dependent and caspase-independent programmed cell death …

Characterization Of Rnai-Defective Mutants—Mut13-2 And Mut20—In Chlamydomonas Reinhardtii, Arit Ghosh

School of Biological Sciences: Dissertations, Theses, and Student Research

RNA interference (RNAi) is a highly conserved and sequence-specific process for regulation of gene expression. At the heart of the RNAi machinery lie 21-24 nt small non-coding RNA molecules which are able to downregulate the expression of cognate sequences, by causing degradation or translational repression of mRNAs. These noncoding RNAs act via the effector RNA-induced silencing complex (RISC), which includes core proteins such as the Argonautes (AGOs). Two Chlamydomonas reinhardtii RNAi-defective mutants, Mut13-2 and Mut20, show deletions of various domains of the Tudor Staphylococcal Nuclease 1 (TSN1) gene. TSN1 has already been recognized as a component of the RNA-induced silencing …

Effects Of Training And Testosterone On Muscle-Fiber Types And Locomotor Performance In Male Six-Lined Racerunners (Aspidoscelis Sexlineata), Jennifer L. O'Conner, Lance D. Mcbrayer, Timothy E. Higham, Jerry F. Husak, Ignacio T. Moore, David C. Rostal

Biology: Faculty Publications

Testosterone (T) is thought to affect a variety of traits important for fitness, including coloration, the size of sexual ornaments, aggression, and locomotor performance. Here, we investigated the effects of experimentally elevated T and locomotor training on muscle physiology and running performance in a nonterritorial male lizard species (Aspidoscelis sexlineata). Additionally, several morphological attributes were quantified to examine other characters that are likely affected by T and/or a training regimen. Neither training alone nor training with T supplementation resulted in increased locomotor performance. Instead, we found that T and training resulted in a decrease in each of three …

Altering Nitric Oxide Bioavailability And Lipid Profiles In Endothelial Cells By Polycyclic Aromatic Hydrocarbons In Particulate Matter, Liang Yu

Theses and Dissertations in Biomedical Sciences

Epidemiologic studies have demonstrated a significant association between exposure to particulate matter (PM) and atherosclerosis. Polycyclic aromatic hydrocarbons (PAHs) present in particulate matter, are well known to induce oxidative stress and lipid peroxidation via generation of reactive oxygen species (ROS). Lipid peroxidation involves regulating endothelial nitric oxide synthase via inhibition of its activity, and as a result, mediates dilation of coronary arterioles is involved with the pathogenesis of atherosclerosis. However, data on assessment of oxidized lipid formation is limited due to low resolution of mass spectrometer methods. Taking the advantage of a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (FT-ICR-MS) …

Identification And Characterization Of A Stilbene Synthase Gene Family In Peanut Hairy Roots, Jose Marcos Condori

Student Theses and Dissertations

Plants produce a large diversity of specialized metabolites in response to biotic and abiotic stimuli. Even though these metabolites are functional to plants as defense compounds, they also show a multitude of benefits in human health. Among these compounds are the stilbenoids. In addition to resveratrol, the most characterized of the stilbenoids, species like peanut produces several prenylated stilbenoids including arachidin-1 and arachidin-3. Recent studies suggest that these prenylated compounds have higher biological activities than resveratrol. Therefore there is a need to understand the mechanisms involved in the biosynthesis of these compounds. Some stilbene synthases involved in the biosynthesis of …