Other Biochemistry, Biophysics, and Structural Biology Commons^™

Functional Analysis Of Legionella Pneumophila Effector Protein, Shreya Neupane

Masters Theses & Specialist Projects

Legionella pneumophila is a gram-negative bacterium that causes Legionnaire’s disease (a severe form of pneumonia) in humans. L. pneumophila can cause infection by utilizing its Type IV secretion system, a protein secretion system that transports proteins from the bacterial cytosol into the infected macrophage. Effectors released from the Type Iv secretion system allow L. pneumophila to create a safe environment to survive, replicate and cause infection. One such effector, RavQ, inhibits cell proliferation of mammalian HEK 293T cells and localizes to the cell’s nucleus, leading us to hypothesize that RavQ interferes with cellular activity in the nucleus. To detect its …

Conformational Flexibility And Local Frustration In The Functional States Of The Sars-Cov-2 Spike B.1.1.7 And B.1.351 Variants: Mutation-Induced Allosteric Modulation Mechanism Of Functional Dynamics And Protein Stability, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Structural and functional studies of the SARS-CoV-2 spike proteins have recently determined distinct functional states of the B.1.1.7 and B.1.351 spike variants, providing a molecular framework for understanding the mechanisms that link the effect of mutations with the enhanced virus infectivity and transmissibility. A detailed dynamic and energetic analysis of these variants was undertaken in the present work to quantify the effects of different mutations on functional conformational changes and stability of the SARS-CoV-2 spike protein. We employed the efficient and accurate coarse-grained (CG) simulations of multiple functional states of the D614G mutant, B.1.1.7 and B.1.351 spike variants to characterize …

Oxidation Alters The Architecture Of The Phenylalanyl-Trna Synthetase Editing Domain To Confer Hyperaccuracy, Pooja Srinivas, Rebecca E. Steiner, Ian J. Pavelich, Ricardo Guerrera-Ferreira, Puneet Juneja, Michael Ibba, Christine M. Dunham

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

High fidelity during protein synthesis is accomplished by aminoacyl-tRNA synthetases (aaRSs). These enzymes ligate an amino acid to a cognate tRNA and have proofreading and editing capabilities that ensure high fidelity. Phenylalanyl-tRNA synthetase (PheRS) preferentially ligates a phenylalanine to a tRNA^Phe over the chemically similar tyrosine, which differs from phenylalanine by a single hydroxyl group. In bacteria that undergo exposure to oxidative stress such as Salmonella enterica serovar Typhimurium, tyrosine isomer levels increase due to phenylalanine oxidation. Several residues are oxidized in PheRS and contribute to hyperactive editing, including against mischarged Tyr-tRNA^Phe, despite these oxidized residues not …

Covid19 Disease Map, A Computational Knowledge Repository Of Virus–Host Interaction Mechanisms, Marek Ostaszewski, Tomáš Helikar, Bhanwar Lal Puniya, A Host Of Co-Authors, Covid-19 Disease Map Community

Department of Biochemistry: Faculty Publications

We need to effectively combine the knowledge from surging literature with complex datasets to propose mechanistic models of SARS-CoV-2 infection, improving data interpretation and predicting key targets of intervention. Here, we describe a large-scale community effort to build an open access, interoperable and computable repository of COVID-19 molecular mechanisms. The COVID-19 Disease Map (C19DMap) is a graphical, interactive representation of disease-relevant molecular mechanisms linking many knowledge sources. Notably, it is a computational resource for graph-based analyses and disease modelling. To this end, we established a framework of tools, platforms and guidelines necessary for a multifaceted community of biocurators, domain experts, …

Itraq-Based Proteomics Analysis And Network Integration For Kernel Tissue Development In Maize, Long Zhang, Yongbin Dong, Qilei Wang, Chunguang Du, Wenwei Xiong, Xinyu Li, Sailan Zhu, Yuling Li

Department of Biology Faculty Scholarship and Creative Works

Grain weight is one of the most important yield components and a developmentally complex structure comprised of two major compartments (endosperm and pericarp) in maize (Zea mays L.), however, very little is known concerning the coordinated accumulation of the numerous proteins involved. Herein, we used isobaric tags for relative and absolute quantitation (iTRAQ)-based comparative proteomic method to analyze the characteristics of dynamic proteomics for endosperm and pericarp during grain development. Totally, 9539 proteins were identified for both components at four development stages, among which 1401 proteins were non-redundant, 232 proteins were specific in pericarp and 153 proteins were specific in …

Protein-Protein Interactions Of Bacterial Topoisomerase I, Srikanth Banda

FIU Electronic Theses and Dissertations

Protein-protein interactions (PPIs) are essential features of cellular processes including DNA replication, transcription, translation, recombination, and repair. In my study, the protein interactions of bacterial DNA topoisomerase I, an essential enzyme, were investigated. The topoisomerase I in bacteria relaxes excess negative supercoiling on DNA and maintains genomic stability. Investigating the PPI network of DNA topoisomerase I can further our understanding of the various functional roles of this enzyme. My study is focused on topoisomerase I of Escherichia coli and Mycobacterium smegmatis. Firstly, we have explored the biochemical mechanisms for an interaction between RNA Polymerase, and topoisomerase I in E. …

Consumption Of High Ω-3 Fatty Acid Diet Suppressed Prostate Tumorigenesis In C3(1) Tag Mice, Juliana A. Akinsete, Gabriela Ion, Theodore R. Witte, W. Elaine Hardman

Biochemistry and Microbiology

Prostate cancer incidence and mortality are high in the Western world and high ω-6/ω-3 PUFA in the Western diet may be a contributing factor. We investigated whether changing from a diet that approximates ω-6 fat content of the Western diet to a high ω-3 fat diet at adulthood might reduce prostate cancer risk. Female SV 129 mice that had consumed a high ω-6 diet containing corn oil for 2 weeks were bred with homozygous C3(1)Tag transgenic male mice. All male offspring were weaned to the corn oil diet (CO) until postpuberty when half of the male offspring were transferred to …

Effects Of Canola And Corn Oil Mimetic On Jurkat Cells, Gabriela Ion, Kayla Fazio, Juliana A. Akinsete, W. Elaine Hardman

Biochemistry and Microbiology

BACKGROUND: The Western diet is high in omega-6 fatty acids and low in omega-3 fatty acids. Canola oil contains a healthier omega 3 to omega 6 ratio than corn oil. Jurkat T leukemia cells were treated with free fatty acids mixtures in ratios mimicking that found in commercially available canola oil (7% α-linolenic, 30% linoleic, 54% oleic) or corn oil (59% linoleic, 24% oleic) to determine the cell survival or cell death and changes in expression levels of inflammatory cytokines and receptors following oil treatment.

METHODS: Fatty acid uptake was assessed by gas chromatography. Cell survival and cell death were …

Maternal Consumption Of Canola Oil Suppressed Mammary Gland Tumorigenesis In C3(1) Tag Mice Offspring, Gabriela Ion, Juliana A. Akinsete, W. Elaine Hardman

Biochemistry and Microbiology

Background: Maternal consumption of a diet high in omega 6 polyunsaturated fats (n-6 PUFA) has been shown to increase risk whereas a diet high in omega 3 polyunsaturated fats (n-3 PUFA) from fish oil has been shown to decrease risk for mammary gland cancer in female offspring of rats. The aim of this study was to determine whether increasing n-3 PUFA and reducing n-6 PUFA by using canola oil instead of corn oil in the maternal diet might reduce the risk for breast cancer in female offspring.

Methods: Female SV 129 mice were divided into two groups and placed on …

Global Analysis Of Gene Expression Changes During Retinoic Acid-Induced Growth Arrest And Differentiation Of Melanoma: Comparison To Differentially Expressed Genes In Melanocytes Vs Melanoma, Mary H. Estler, Goran Boskovic, James Denvir, Sarah Miles, Donald A. Primerano, Richard M. Niles

Biochemistry and Microbiology

BACKGROUND: The incidence of malignant melanoma has significantly increased over the last decade. Some of these malignancies are susceptible to the growth inhibitory and pro-differentiating effects of all-trans-retinoic acid (RA). The molecular changes responsible for the biological activity of RA in melanoma are not well understood.

RESULTS: In an analysis of sequential global gene expression changes during a 4-48 h RA treatment of B16 mouse melanoma cells, we found that RA increased the expression of 757 genes and decreased the expression of 737 genes. We also compared the gene expression profile (no RA treatment) between non-malignant melan-a mouse melanocytes and …

The Epigenomic Viewpoint On Cellular Differentiation Of Myeloid Progenitor Cells As It Pertains To Leukemogenesis, Vincent E. Sollars

Biochemistry and Microbiology

The new millennium has brought with it a surge of research in the field of epigenetics. This has included advances in our understanding of stem cell characteristics and mechanisms of commitment to cell lineages prior to differentiation. The nature of stem cells is similar to that of malignant cells in that they have unlimited self-renewal and protection from apoptosis, leading researchers to suspect that stem cells are the target of oncogenesis. This review will explore the idea of how epigenetic control of gene expression may contribute to mechanisms controlling differentiation of myeloid progenitor cells and its importance to our understanding …

Evidence For An Epigenetic Mechanism By Which Hsp90 Acts As A Capacitor For Morphological Evolution, Vincent E. Sollars, Xiangyi Lu, Li Xiao, Xiaoyan Wang, Mark D. Garfinkel, Douglas M. Ruden

Biochemistry and Microbiology

Morphological alterations have been shown to occur in Drosophila melanogaster when function of Hsp90 (heat shock 0-kDa protein 1α, encoded by Hsp83) is compromised during development1. Genetic selection maintains the altered phenotypes in subsequent generations1. Recent experiments have shown, however, that phenotypic variation still occurs in nearly isogenic recombinant inbred strains of Arabidopsis thaliana2. Using a sensitized isogenic D. melanogaster strain, iso-KrIf-1, we confirm this finding and present evidence supporting an epigenetic mechanism for Hsp90’s capacitor function, whereby reduced activity of Hsp90 induces a heritably altered chromatin state. The altered chromatin state is evidenced by ectopic expression …

Serotyping Group B Streptococci In A Small Community Hospital: An Analysis Of Distribution And Site Of Isolation, Jennifer M. Smith, Jason A. Rexroth, David G. Chaffin, Susan H. Jackman

Biochemistry and Microbiology

Objective: To determine the prevalence and site of isolation of different serotypes of group B streptococcus (GBS) colonization or infection at a small community hospital.

Methods: GBS isolates were obtained from a small community hospital and were then serotyped as la, Ib, II, III, IV, V or non-typeable. Hospital records were reviewed for patient sex, age and pregnancy status as well as the site of GBS isolation.

Results: GBS serotypes Ia, III and V were most common and accounted for over 60% of the total number of isolates. Serotype Ia was most prevalent in reproductive-age females, while serotypes V and …

Murine Epidermal Cell Antigen (Skn)-Directed Autoimmunity Induced By Transfer Of Cd4+ T Cells, Susan H. Jackman, Shivaleela Keerthy, Giselle Perry

Biochemistry and Microbiology

While pathogenic T cells have been identified for several diseases with epithelial cell damage, an autoimmune T cell-mediated response targeted against a known keratinocyte antigen has not been reported. Previously we described an autoimmune response directed to the mouse epidermal cell antigens, Skn. For our murine model, primed Skn-immune lymphocytes are adoptively transferred to recipients, which develop lesions at the site of mild skin trauma. In this study we investigated the nature of the autoimmune component of the Skn response. A time-course study demonstrated a relationship between the number of primed Sknimmune cells injected and the severity of skin lesions …