Biochemistry, Biophysics, and Structural Biology Commons^™

Autoimmunity In Picornavirus Infections, Chandirasegara Massilamany, Andreas Koenig, Jay Reddy, Sally Huber, Iwona Buskiewicz

School of Veterinary and Biomedical Sciences: Faculty Publications

Enteroviruses are small, non-enveloped, positive-sense singlestrand RNA viruses, and are ubiquitously found throughout the world. These viruses usually cause asymptomatic or mild febrile illnesses, but have a propensity to induce severe diseases including type 1 diabetes and pancreatitis, paralysis and neuroinflammatory disease, myocarditis, or hepatitis. This pathogenicity may result from induction of autoimmunity to organ-specific antigens. While enterovirus-triggered autoimmunity can arise from multiple mechanisms including antigenic mimicry and release of sequestered antigens, the recent demonstration of T cells expressing dual T cell receptors arising as a natural consequence of Theiler’s virus infection is the first demonstration of this autoimmune mechanism.

Genome-Wide Search For Host Association Factors During Ovine Progressive Pneumonia Virus Infection, Jesse Thompson, Fangrui Ma, Meghan Quinn, Shi-Hua Xiang

School of Veterinary and Biomedical Sciences: Faculty Publications

Ovine progressive pneumonia virus (OPPV) is an important virus that causes serious diseases in sheep and goats with a prevalence of 36% in the USA. Although OPPV was discovered more than half of a century ago, little is known about the infection and pathogenesis of this virus. In this report, we used RNA-seq technology to conduct a genome-wide probe for cellular factors that are associated with OPPV infection. A total of approximately 22,000 goat host genes were detected of which 657 were found to have been significantly up-regulated and 889 down-regulated at 12 hours post-infection. In addition to previously known …

Guidelines For The Use And Interpretation Of Assays For Monitoring Autophagy (3rd Edition), Daniel J. Klionsky, Rodrigo Franco, More Than 2,000 Co-Authors

School of Veterinary and Biomedical Sciences: Faculty Publications

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes.

For example, a key point that needs to be emphasized is that …

From Crystal Structure Of Α-Conotoxin Gic In Complex With Ac-Achbp To Molecular Determinants Of Its High Selectivity For Α3Β2 Nachr, Bo Lin, Manyu Xu, Xiaopeng Zhu, Yong Wu, Xi Liu, Dongting Zhangsun, Yuanyan Hu, Shi-Hua Xiang, Igor E. Kasheverov, Victor I. Tsetlin, Xinquan Wang, Sulan Luo

School of Veterinary and Biomedical Sciences: Faculty Publications

Acetylcholine binding proteins (AChBPs) are unique spatial homologs of the ligand-binding domains of nicotinic acetylcholine receptors (nAChRs), and they reproduce some pharmacological properties of nAChRs. X-ray crystal structures of AСhBP in complex with α-conotoxins provide important insights into the interactions of α-conotoxins with distinct nAChR subtypes. Although considerable efforts have been made to understand why α-conotoxin GIC is strongly selective for α3β2 nAChR, this question has not yet been solved. Here we present the structure of α-conotoxin GIC in complex with Aplysia californica AChBP (Ac-AChBP) at a resolution of 2.1 Å. Based on this co-crystal structure complemented with molecular docking …

From Crystal Structure Of Α-Conotoxin Gic In Complex With Ac-Achbp To Molecular Determinants Of Its High Selectivity For Α3Β2 Nachr, Bo Lin, Manyu Xu, Xiaopeng Zhu, Yong Wu, Xi Liu, Dongting Zhangsun, Yuanyan Hu, Shi-Hua Xiang, Igor E. Kasheverov, Victor I. Tsetlin, Xianquan Wang, Sulan Luo

School of Veterinary and Biomedical Sciences: Faculty Publications

Acetylcholine binding proteins (AChBPs) are unique spatial homologs of the ligand-binding domains of nicotinic acetylcholine receptors (nAChRs), and they reproduce some pharmacological properties of nAChRs. X-ray crystal structures of AСhBP in complex with α-conotoxins provide important insights into the interactions of α-conotoxins with distinct nAChR subtypes. Although considerable efforts have been made to understand why α-conotoxin GIC is strongly selective for α3β2 nAChR, this question has not yet been solved. Here we present the structure of α-conotoxin GIC in complex with Aplysia californica AChBP (Ac-AChBP) at a resolution of 2.1 Å. Based on this co-crystal structure complemented with molecular docking …

A Synthetic Porcine Reproductive And Respiratory Syndrome Unprecedented Levels Of Heterologous Protection, Hiep Vu, Fangrui Ma, William W. Laegreid, Asit K. Pattnaik, David Steffen, Alan R. Doster, Fernando A. Osorio

School of Veterinary and Biomedical Sciences: Faculty Publications

Current vaccines do not provide sufficient levels of protection against divergent porcine reproductive and respiratory syndrome virus (PRRSV) strains circulating in the field, mainly due to the substantial variation of the viral genome. We describe here a novel approach to generate a PRRSV vaccine candidate that could confer unprecedented levels of heterologous protection against divergent PRRSV isolates. Using a set of 59 non-redundant, full genome sequences of type-2 PRRSV, a consensus genome (designated as PRRSV-CON) was these 59 PRRSV full genome sequences, followed by selecting the most common nucleotide found at each position of the alignment. Next, the synthetic PRRSV-CON …

Overview Of Rhabdo- And Filoviruses, Asit K. Pattnaik, Michael A. Whitt

School of Veterinary and Biomedical Sciences: Faculty Publications

Enveloped viruses with a negative-sense, single-stranded monopartite RNA genome have been classified into the order Mononegavirales. Five families of viruses that constitute the order are: Rhabdoviridae, Filoviridae, Paramyxoviridae, Bornaviridae and Nyamiviridae. Members of these families possess a helical nucleocapsid core containing the viral genome and a host-derived lipid envelope containing viral proteins. This introductory chapter provides a brief overview of the Rhabdoviridae and the Filoviridae, the two families of viruses that are the subject of this book. Many members of these two families are highly significant human and animal pathogens. The rationale and goal of the book is to …

On And Off Retinal Ganglion Cells Differentially Regulate Serotonergic And Gabaergic Activity In The Dorsal Raphe Nucleus, Ting Zhang, Lu Huang, Li Zhang, Minjie Tan, Mingliang Pu, Gary E. Pickard, Kwok -Fai So, Chaoran Ren

School of Veterinary and Biomedical Sciences: Faculty Publications

The dorsal raphe nucleus (DRN), the major source of serotonergic input to the forebrain, receives excitatory input from the retina that can modulate serotonin levels and depressive-like behavior. In the Mongolian gerbil, retinal ganglion cells (RGCs) with alpha-like morphological and Y-like physiological properties innervate the DRN with ON DRN-projecting RGCs out numbering OFF DRN-projecting RGCs. The DRN neurons targeted by ON and OFF RGCs are unknown. To explore retino-raphe anatomical organization, retinal afferents labeled with Cholera toxin B were examined for association with the postsynaptic protein PSD-95. Synaptic associations between retinal afferents and DRN serotonergic and GABAergic neurons were observed. …

Whole Genomic Sequence Analysis Of Bacillus Infantis: Defining The Genetic Blueprint Of Strain Nrrl B-14911, An Emerging Cardiopathogenic Microbe, Chandirasegara Massilamany, Akram Mohammed, John Dustin Loy, Tanya Purvis, Bharathi Krishnan, Rakesh H. Basavalingappa, Christy M. Kelley, Chittibabu Guda, Raúl G. Barletta, Etsuko N. Moriyama, Timothy P.L. Smith, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

Background: We recently reported the identification of Bacillus sp. NRRL B-14911 that induces heart autoimmunity by generating cardiac-reactive T cells through molecular mimicry. This marine bacterium was originally isolated from the Gulf of Mexico, but no associations with human diseases were reported. Therefore, to characterize its biological and medical significance, we sought to determine and analyze the complete genome sequence of Bacillus sp. NRRL B-14911.

Results: Based on the phylogenetic analysis of 16S ribosomal RNA (rRNA) genes, sequence analysis of the 16S-23S rDNA intergenic transcribed spacers, phenotypic microarray, and matrix-assisted laser desorption ionization time-offlight mass spectrometry, we propose that this …

Host Cell Functions In Vesicular Stomatitis Virus Replication, Phat X. Dinh, Anshuman Das, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

Vesicular stomatitis virus (VSV), the prototypic rhabdovirus, has been used as an excellent paradigm for understanding the mechanisms of virus replication, pathogenesis, host response to virus infection and also for myriads of studies on cellular and molecular biology. Biochemical studies as well as high-throughput genomics, proteomics, and chemical approaches have revealed a plethora of cellular factors and pathways that regulate replication of VSV. These factors include those that support virus replication and also those that restrict its replication. This chapter discusses the role(s) of many of these host cell factors and pathways involved in VSV replication. Although mechanistic understanding of …

Erratum To: Association Of Autophagy In The Cell Death Mediated By Dihydrotestosterone In Autoreactive T Cells Independent Of Antigenic Stimulation, Ting Jia, Anandhan Annadurai, Chandirasegara Massilamany, Rajkumar A. Rajasekaran, Rodrigo Franco, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

No abstract provided.

New Tools To Convert Bacterial Artificial Chromosomes To A Self-Excising Design And Their Application To A Herpes Simplex Virus Type 1 Infectious Clone, Alexsia L. Richards, Patricia J. Sollars, Gregory A. Smith

School of Veterinary and Biomedical Sciences: Faculty Publications

Background: Infectious clones are fundamental tools for the study of many viruses, allowing for efficient mutagenesis and reproducible production of genetically-defined strains. For the large dsDNA genomes of the herpesviridae, bacterial artificial chromosomes have become the cloning vector of choice due to their capacity to house full-length herpesvirus genomes as single contiguous inserts. Furthermore, while maintained as plasmids in Escherichia coli, the clones can be mutated using robust prokaryotic recombination systems. An important consideration in the design of these clones is the means by which the vector backbone is removed from the virus genome upon delivery into mammalian cells. …

Resolving Bovine Viral Diarrhea Virus Subtypes From Persistently Infected U.S. Beef Calves With Complete Genome Sequence, Aspen M. Workman, Michael P. Heaton, Gregory P. Harhay, Timothy P.L. Smith, Dale M. Grotelueschen, David Sjeklocha, Bruce Brodersen, Jessica L. Petersen, Carol G. Chitko-Mckown

School of Veterinary and Biomedical Sciences: Faculty Publications

Bovine viral diarrhea virus (BVDV) is classified into 2 genotypes, BVDV-1 and BVDV-2, each of which contains distinct subtypes with genetic and antigenic variation. To effectively control BVDV by vaccination, it is important to know which subtypes of the virus are circulating and how their prevalence is changing over time. Accordingly, the purpose of our study was to estimate the current prevalence and diversity of BVDV subtypes from persistently infected (PI) beef calves in the central United States. Phylogenetic analysis of the 5′-UTR (5′ untranslated region) for 119 virus strains revealed that a majority (82%) belonged to genotype 1b, and …

Maporal Hantavirus Causes Mild Pathology In Deer Mice (Peromyscus Maniculatus), Amanda Mcguire, Kaitlyn Miedema, Joseph R. Fauver, Amber Rico, Tawfik Aboellail, Sandra L. Quackenbush, Ann Hawkinson, Tony Schountz

School of Veterinary and Biomedical Sciences: Faculty Publications

Rodent-borne hantaviruses can cause two human diseases with many pathological similarities: hantavirus cardiopulmonary syndrome (HCPS) in the western hemisphere and hemorrhagic fever with renal syndrome in the eastern hemisphere. Each virus is hosted by specific reservoir species without conspicuous disease. HCPS-causing hantaviruses require animal biosafety level-4 (ABSL-4) containment, which substantially limits experimental research of interactions between the viruses and their reservoir hosts. Maporal virus (MAPV) is a South American hantavirus not known to cause disease in humans, thus it can be manipulated under ABSL-3 conditions. The aim of this study was to develop an ABSL-3 hantavirus infection model using the …

The Mechanistic Basis Of Hemoglobin Adaptation In The High-Flying Barheaded Goose: Insights From Ancestral Protein Resurrection, Chandrasekhar Natarajan, Amit Kumar, Hideaki Moriyama, Roy E. Weber, Angela Fago, Jay F. Storz

School of Veterinary and Biomedical Sciences: Faculty Publications

The bar-headed goose (‘BHG’, Anser indicus) is renowned for its trans-Himalayan migratory flights, and the elevated hemoglobin (Hb)-O2 affinity of this species is thought to make a key contribution to its capacity for powered flight at elevations of ~9000 m. Here we revisit the molecular basis of this text-book example of biochemical adaptation. Previous hypotheses about the molecular basis of the evolved increase in Hb-O2 affinity were tested by engineering BHGspecific mutations into recombinant human Hb. This approach can provide important insights, but one problem with such ‘horizontal’ comparisons – swapping residues between proteins of contemporary species – is that …

Localization Of Cd8 T Cell Epitope Within Cardiac Myosin Heavy Chain-Α334-352 That Induces Autoimmune Myocarditis In A/J Mice, Chandirasegara Massilamany, Arunakumar Gangaplara, Rakesh H. Basavalingappa, Rajkumar A. Rajasekaran, Vahid Khalilzad-Sharghi, Zhongji Han, Shadi F. Othman, David Steffen, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

Background—Cardiac myosin heavy chain-α (Myhc), an intracellular protein expressed in the cardiomyocytes, has been identified as a major autoantigen in cardiac autoimmunity. In our studies with Myhc_334-352-induced experimental autoimmune myocarditis in A/J mice (H-2a), we discovered that Myhc_334-352, supposedly a CD4 T cell epitope, also induced antigen-specific CD8 T cells that transfer disease to naïve animals.

Methods and Results—In our efforts to identify the CD8 T cell determinants, we localized Myhc_338-348 within the full length-Myhc_334-352, leading to four key findings. (1) By acting as a dual epitope, Myhc_338-348 induces both …

Visualizing Herpesvirus Procapsids In Living Cells, Oana Maier, Patricia J. Sollars, Gary E. Pickard, Gregory A. Smith

School of Veterinary and Biomedical Sciences: Faculty Publications

A complete understanding of herpesvirus morphogenesis requires studies of capsid assembly dynamics in living cells. Although fluorescent tags fused to the VP26 and pUL25 capsid proteins are available, neither of these components is present on the initial capsid assembly, the procapsid. To make procapsids accessible to live-cell imaging, we made a series of recombinant pseudorabies viruses that encoded green fluorescent protein (GFP) fused in frame to the internal capsid scaffold and maturation protease. One recombinant, a GFP-VP24 fusion, maintained wild-type propagation kinetics in vitro and approximated wild-type virulence in vivo. The fusion also proved to be well tolerated in …

Note On Ehrlichia Chaffeensis, Ehrlichia Ewingii, And “Borrelia Lonestari” Infection In Lone Star Ticks (Acari: Ixodidae), Nebraska, Usa, Amanda Maegli, J. Dustin Loy, Roberto Cortinas

School of Veterinary and Biomedical Sciences: Faculty Publications

The lone star tick, Amblyomma americanum (L.) (Acari: Ixodidae), is established in southeastern Nebraska, yet the prevalence of tick-associated microorganisms is not known. An initial PCR-based analysis for Ehrlichia chaffeensis, Ehrlichia ewingii, and Borrelia infection in host-seeking adult ticks collected in southeast Nebraska was conducted. A total of 251 adult ticks collected in six sites in southeast Nebraska were tested. E. chaffeensis, E. ewingii, and Borrelia spp. were present, and the prevalence of each was approximately 1.6%. This study demonstrates that Ehrlichia spp. are present in Nebraska lone star tick populations.

Expression And Distribution Of Thiol-Regulating Enzyme Glutaredoxin 2 (Grx2) In Porcine Ocular Tissues, Bijaya Upadhyaya, Xiaoli Tian, Hongli Wu, Marjorie F. Lou

School of Veterinary and Biomedical Sciences: Faculty Publications

Glutaredoxin2 (Grx2) is a mitochondrial isozyme of the cytosolic glutaredoxin1 (thioltransferase or TTase). Both belong to the large oxidoreductase family and play an important role in maintaining thiol/disulfide redox homeostasis in the cells. Grx2 is recently found in the lens where its activities of disulfide reductase and peroxidase, similar to TTase, can protect the lens against oxidative stress. Since other eye tissues are also highly sensitive to oxidative stress, and TTase’s distribution in the eye is known, we focused on this study by investigating the Grx2 distribution in the ocular tissues in comparison to the lens. Fresh porcine eyes were …

Analysis Of Mycobacterium Avium Subsp. Paratuberculosis Mutant Libraries Reveals Loci-Dependent Transposition Biases And Strategies For Novel Mutant Discovery, Govardhan Rathnaiah, John Bannantine, Darrell O. Bayles, Denise K. Zinniel, Judith R. Stabel, Yrjö T. Gröhn, Raúl G. Barletta

School of Veterinary and Biomedical Sciences: Faculty Publications

Mycobacterium avium subsp. paratuberculosis (MAP), the aetiological agent of Johne’s disease, is one of the most important bacterial pathogens in ruminants. A thorough understanding of MAP pathogenesis is needed to develop new vaccines and diagnostic tests. The generation of comprehensive random transposon mutant libraries is a fundamental genetic technology to determine the role of genes in physiology and pathogenesis. In this study, whole MAP genome analysis compared the insertion sites for the mycobacterial transposon Tn5367 derived from the Mycobacterium smegmatis insertion sequence IS1096 and the mariner transposon MycoMarT7 carrying the Himar1 transposase. We determined that only MycoMarT7 provides …

Mosquito Host Choices On Livestock Amplifiers Of Rift Valley Fever Virus In Kenya, David P. Tchouassi, Robinson O. Okiro, Rosemary Sang, Lee W. Cohnstaedt, D. Scott Mcvey, Baldwyn Torto

School of Veterinary and Biomedical Sciences: Faculty Publications

Background: Animal hosts may vary in their attraction and acceptability as components of the host location process for assessing preference, and biting rates of vectors and risk of exposure to pathogens. However, these parameters remain poorly understood for mosquito vectors of the Rift Valley fever (RVF), an arboviral disease, and for a community of mosquitoes.

Methods: Using three known livestock amplifiers of RVF virus including sheep, goat and cattle as bait in enclosure traps, we investigated the host-feeding patterns for a community of mosquitoes in Naivasha, an endemic area of Rift Valley fever (RVF), in a longitudinal study for six …

Suppression Of Nlrp3 Inflammasome By Γ-Tocotrienol Ameliorates Type 2 Diabetes, Yongeun Kim, Wei Wang, Meshail Okla, Inhae Kang, Regis Moreau, Soonkyu Chung

Department of Nutrition and Health Sciences: Faculty Publications

The Nod-like receptor 3 (NLRP3) inflammasome is an intracellular sensor that sets off the innate immune system in response to microbial-derived and endogenous metabolic danger signals. We previously reported that γ-tocotrienol (γT3) attenuated adipose tissue inflammation and insulin resistance in diet-induced obesity, but the underlying mechanism remained elusive. Here, we investigated the effects of γT3 on NLRP3 inflammasome activation and attendant consequences on type 2 diabetes. γT3 repressed inflammasome activation, caspase-1 cleavage, and interleukin (IL) 1β secretion in murine macrophages, implicating the inhibition of NLRP3 inflammasome in the anti-inflammatory and antipyroptotic properties of γT3. Furthermore, supplementation of leptin-receptor KO mice …

Effect Of Two-Year Caloric Restriction On Bone Metabolism And Bone Mineral Density In Non-Obese Younger Adults: A Randomized Clinical Trial, Dt Villareal, L Fontana, Sk Das, Et Al.

Faculty, Staff and Students Publications

Although caloric restriction (CR) could delay biologic aging in humans, it is unclear if this would occur at the cost of significant bone loss. We evaluated the effect of prolonged CR on bone metabolism and bone mineral density (BMD) in healthy younger adults. Two-hundred eighteen non-obese (body mass index [BMI] 25.1?±?1.7?kg/m(2) ), younger (age 37.9?±?7.2 years) adults were randomly assigned to 25% CR (CR group, n?=?143) or ad libitum (AL group, n?=?75) for 2 years. Main outcomes were BMD and markers of bone turnover. Other outcomes included body composition, bone-active hormones, nutrient intake, and physical activity. Body weight (-7.5?±?0.4 versus …

Piperlongumine (Piplartine) And Analogues: Antiproliferative Microtubule-Destabilising Agents, Mary J. Meegan, Seema M. Nathwani, Brendan Twamley, Daniela M. Zisterer, Niamh O'Boyle

Articles

Piperlongumine (piplartine, 1) is a small molecule alkaloid that is receiving intense interest due to its antiproliferative and anticancer activities. We investigated the effects of 1 on tubulin and microtubules. Using both an isolated tubulin assay, and a combination of sedimentation and Western blotting, we demonstrated that 1 is a tubulin-destabilising agent. This result was confirmed by immunofluorescence and confocal microscopy, which showed that microtubules in MCF-7 breast cancer cells were depolymerised when treated with 1. We synthesised a number of analogues of 1 to explore structure-activity relationships. Compound 13 had the best cytotoxic profile of this series, …

Structural Characterization And Therapeutic Utility Of The Proton-Coupled Folate Transporter, Michael Roy Wilson

Wayne State University Dissertations

Folate is a B9 vitamin essential to DNA synthesis. The proton-coupled folate transporter (PCFT) is a newly discovered proton/folate symporter with an acidic pH optimum and broad expression across a variety of solid tumor types, with limited expression in normal tissues. Several antifolate molecules have been developed as cancer therapeutics, although these classical antifolates display numerous off-target effects due to transport by the ubiquitous reduced folate carrier (RFC). In this dissertation, we determine the roles of multiple PCFT structure/function domains, and develop PCFT-specific antifolates to target solid tumors. We utilize substituted cysteine accessibility methods (SCAM) to identify a novel reentrant …

Understanding Dna Condensation By Low Generation (G0/G1) And Zwitterionic G4 Pamam Dendrimers, Min An

Theses and Dissertations--Chemistry

Cationic polymers have shown potential as gene delivery vectors due to their ability to condense DNA and protect it from cellular and restriction nucleases. Dendrimers are hyperbranched macromolecules with precisely defined molecular weights and highly symmetric branches stemming from a central core. The nanosize, tunable surface chemistries and ease of surface functionalization has made dendrimers an attractive alternative to conventional linear polymers for DNA delivery applications. The commercially available, cationic dendrimer poly(amidoamine) or PAMAM is the most widely studied dendrimer for use as a gene delivery vector. The aim of this dissertation is to provide an increased understanding of the …

Artemisinin Production By Plant Hairy Root Cultures In Gas- And Liquid-Phase Bioreactors, Nivedita Patra, Ashok K. Srivastava

Articles

Key message

Alternative biotechnological protocol for large-scale artemisinin production was established. It featured enhanced growth and artemisinin production by cultivation of hairy roots in nutrient mist bioreactor (NMB) coupled with novel cultivation strategies.

Artemisinin is used for the treatment of cerebral malaria. Presently, its main source is from seasonal plant Artemisia annua. This study featured investigation of growth and artemisinin production by A. annua hairy roots (induced by Agrobacterium rhizogenes-mediated genetic transformation of explants) in three bioreactor configurations—bubble column reactor, NMB and modified NMB particularly to establish their suitability for commercial production. It was observed that cultivation of …

Probing Allosteric, Partial Inhibition Of Thrombin Using Novel Anticoagulants, Stephen S. Verespy Iii

Theses and Dissertations

Thrombin is the key protease that regulates hemostasis; the delicate balance between procoagulation and anticoagulation of blood. In clotting disorders, like deep vein thrombosis or pulmonary embolism, procoagulation is up-regulated, but propagation of clotting can be inhibited with drugs targeting the proteases involved, like thrombin. Such drugs however, have serious side effects (e.g., excessive bleeding) and some require monitoring during the course of treatment. The reason for these side effects is the mechanism by which the drugs’ act. The two major mechanisms are direct orthosteric and indirect allosteric inhibition, which will completely abolish the protease’s activity. Herein we sought an …

The Study Of The Regulon Of Oxyr In Escherichia Coli And Porphyromonas Gingivalis, Christopher K. Pham

Theses and Dissertations

The facultative anaerobe, Escherichia coli and the obligate anaerobe, Porphyromonas gingivalis are two bacteria that reside in our body. Although they reside in separate environments, they are both subject to hydrogen peroxide stress and have mechanisms to regulate the stress. OxyR is the primary transcriptional regulator/sensor of oxidative stress response caused by hydrogen peroxide. OxyR in P. gingivalis is not well-characterized compared to OxyR in E. coli. We sought to characterize and compare the two forms of OxyR in order to gain a better understanding of the protein. We determined the oligomeric state of both proteins: primarily a tetramer for …

Resolution Of Inflammation Rescues Axon Initial Segment Disruption, Nicholas M. George

Theses and Dissertations

Axonal domains are required for proper neuron function. These domains are unstable and degenerate concurrent with the inflammation in multiple sclerosis (MS) and the inflammatory disease models experimental autoimmune encephalomyelitis (EAE) and lipopolysaccharide (LPS) induced inflammation. Previous studies from our laboratory have shown that the axon initial segment (AIS) is maintained independently of the presence of myelin, but that AIS disruption is seen in MS as well as EAE and LPS-mediated inflammation. AIS loss can be interrupted in the early stage of EAE using the anti-inflammatory drug Didox. However, the potential for Didox directed repair of the AIS in later …