Biochemistry, Biophysics, and Structural Biology Commons^™

Dcaf14 Regulates Cdt2 To Promote Set8-Dependent Replication Fork Protection, Neysha Tirado-Class, Caitlin Hathaway, Anthony Nelligan, Huzefa Dungrawala

Molecular Biosciences Faculty Publications

DDB1- and CUL4-associated factors (DCAFs) CDT2 and DCAF14 are substrate receptors for Cullin4–RING E3 ubiquitin ligase (CRL4) complexes. CDT2 is responsible for PCNA-coupled proteolysis of substrates CDT1, p21, and SET8 during S-phase of cell cycle. DCAF14 functions at stalled replication forks to promote genome stability, but the mechanism is unknown. We find that DCAF14 mediates replication fork protection by regulating CRL4CDT2 activity. Absence of DCAF14 causes increased proteasomal degradation of CDT2 substrates. When forks are challenged with replication stress, increased CDT2 function causes stalled fork collapse and impairs fork recovery in DCAF14-deficient conditions. We further show that stalled fork protection …

Otud5 Limits Replication Fork Instability By Organizing Chromatin Remodelers, Angelo De Vivo, Hongseon Song, Yujin Lee, Neysha Tirado-Class, Anthony Sanchez, Sandy D. Westerheide, Huzefa Dungrawala, Younghoon Kee

Molecular Biosciences Faculty Publications

Proper regulation of replication fork progression is important for genomic maintenance. Subverting the transcription-induced conflicts is crucial in preserving the integrity of replication forks. Various chromatin remodelers, such as histone chaperone and histone deacetylases are known to modulate replication stress, but how these factors are organized or collaborate are not well understood. Here we found a new role of the OTUD5 deubiquitinase in limiting replication stress. We found that OTUD5 is recruited to replication forks, and its depletion causes replication fork stress. Through its C-terminal disordered tail, OTUD5 assembles a complex containing FACT, HDAC1 and HDAC2 at replication forks. A …

The Identification Of Two M20b Family Peptidases Required For Full Virulence In Staphylococcus Aureus, Nathanial James Torres, Devon Rizzo, Maria A. Reinberg, Mary-Elizabeth Jobson, Brendan C. Totzke, Jessica K. Jackson, Wenqi Yu, Lindsey Neil Shaw

Molecular Biosciences Faculty Publications

We have previously demonstrated that deletion of an intracellular leucine aminopeptidase results in attenuated virulence of S. aureus. Herein we explore the role of 10 other aminopeptidases in S. aureus pathogenesis. Using a human blood survival assay we identified mutations in two enzymes from the M20B family (PepT1 and PepT2) as having markedly decreased survival compared to the parent. We further reveal that pepT1, pepT2 and pepT1/2 mutant strains are impaired in their ability to resist phagocytosis by, and engender survival within, human macrophages. Using a co-infection model of murine sepsis, we demonstrate impairment of dissemination and survival …

S-Acylation Is A Key Regulator Of Orai1/Stim1-Mediated Store-Operated Calcium Entry In T Cells, Savannah J. West Diaz

Dissertations and Theses (Open Access)

Orai1 and STIM1 proteins are the essential components of the Ca²⁺ release activated Ca²⁺ (CRAC) channel which is required for store-operated Ca²⁺ entry (SOCE) in T cells and subsequent signaling events leading to T cell activation, proliferation, and differentiation. Plasma membrane (PM)-localized Orai1 is the pore-forming subunit of the CRAC channel, and STIM1 is the Ca²⁺ sensor localized to the endoplasmic reticulum (ER) membrane in quiescent T cells. T cell receptor (TCR) stimulation leads to depletion of ER Ca²⁺ stores resulting in Ca²⁺ no longer being bound to STIM1. This activates STIM1 by triggering …

Tagging Atg5 With An Epitope Tag To Measure The Amount Of Atg12-5 Conjugation In Atg10 Mutants, Sophie Campbell

Senior Honors Theses and Projects

Autophagy is a necessary recycling process that occurs in cells, but the functions of the proteins that carry this out are not completely understood. The protein ATG10 has a distinct role in forming autophagosomes, large double membrane vesicles necessary for this process. ATG10 forms a covalent bond between the proteins ATG12 and ATG5 but its final effect on autophagosome formation is still unclear. We are using DNA manipulation techniques to add a myc epitope tag to yeast ATG5 which will allow us to measure the effect of atg10 mutants on ATG12-5 conjugation via Western Blot. These results will help us …

Establishing A Biochemical System For The Purification And Atpase Activity Of Gst-Dbp5, Sarah Utley, Rachel E. Rigsby Phd, Rebecca L. Adams Phd

Science University Research Symposium (SURS)

The export of mRNA out of the nucleus is a crucial step for eukaryotic gene expression. The export of mRNA transcripts is aided by Mex67, which allows export through the nuclear pore complex doorways in the nuclear envelope. Once out of the nucleus, a protein known as Dbp5, bound to ATP, Gle1, and Nup42 aids in the directionality of mRNA export by helping remove Mex67 from the mRNA strand. Following interaction with RNA, Dbp5 then hydrolyzes ATP so that it unbinds the mRNA, allowing for enzyme recycling. The goal of this study is to explore the ATPase activity of Saccharomyces …

Detecting Linc Complex Mps3 And Nuclear Pore Complex Ndj1 Protein Interactions On Yeast Nuclear Membrane S Through Fluorescence Microscopy, Dean Boecher, Rebecca Adams

Science University Research Symposium (SURS)

Though cancer cells have been shown to have abnormal nuclear morphologies and responses to mechanical forces, the mechanisms of how mechanical stress is translated into cellular action and structural reorganization within the nuclear envelope are largely unexplored. The Linker of Nucleoskeleton and Cytoskeleton (LINC) complex is a transmembrane protein complex that connects the actin cytoskeleton to the lamin nucleoskeleton, enabling mechanical forces to be translated between the cytoplasm and the nucleus. In cells exposed to physical stress, nuclear pore complexes (NPCs) –which control the exchange of biochemical signals and macromolecules in and out of the nucleus through mRNA export –have …

Analyzing Mex67 Interaction With The Ssa4 Transcript For Selective Export, Gretchen E. Stalnaker, Rebecca Adams

Science University Research Symposium (SURS)

In eukaryotic cells, such as the budding yeast Saccharomyces cerevisiae, mRNA export is the essential process in which mature mRNA is transported from its site of production, the nucleus, through the nuclear pore complex (NPC) to the cytoplasm, where it can then be translated into protein. This is accomplished when a transcript interacts with the mRNA export protein Mex67, which shuttles the message across the NPC. When the cell is under conditions of stress, such as heat shock, most mRNA export is prohibited, allowing for selective gene expression that prioritizes cell recovery. Specifically, SSA4, which encodes a protein that …

Testing Ssa4:Ade3 Reporters For Mcs Screening, Karah Edmonds, Rebecca Adams

Science University Research Symposium (SURS)

In eukaryotic cells, after transcription, mRNA is escorted from the nucleus to the cytoplasm to be translated. This process, called mRNA export, is essential for gene expression. However, when the cell exists in stressful conditions, mRNA export becomes regulated, and only select transcripts, including the stress-responsive SSA4 mRNA, can be exported. This project aims to uncover the mechanism of selective SSA4 mRNA export by generating a reporter that enables phenotypically visible expression under stressful conditions. Specifically, the ADE3 ORF was placed under the regulatory sequence of SSA4, which was anticipated to induce a red color for colonies only following stress. …

Identification Of Rickettsia Prowazekii Methionine Aminopeptidase Inhibitors And Development Of Thermal Shift Assays For Burkholderia Pseudomallei Ispf And Sars-Cov-2 3cl Protease, Ishpriya Sharma

Graduate Research Theses & Dissertations

There is a crucial need for new antibacterial agents to combat the increase in antibiotic resistance. Methionine aminopeptidase (MetAp) is an enzyme that removes the amino-terminal methionine residue from newly synthesized proteins, an important step in the maturation of proteins. As such, MetAp is a target for the development of antibacterial and anticancer agents. One such bacterial target is Rickettsia prowazekii (Rp), the causative agent of epidemic typhus. To discover new inhibitors of RpMetAp1, the MMV Malaria Box, which is a collection of 400 compounds with drug-like and probe-like compounds, was screened using a high throughput fluorescence-based RpMetAp1 enzyme inhibition …

Rnai-Mediated Gene Silencing In The Exotic Redbay Ambrosia Beetle, Xyleborus Glabratus, And Insect-Fungal Interactions Within The Laurel Wilt Complex, Morgan Christine Knutsen

Theses and Dissertations--Entomology

Laurel wilt disease (LWD) is a lethal vascular disease impacting lauraceous hosts caused by Harringtonia lauricola, the fungal symbiont of the redbay ambrosia beetle (Xyleborus glabratus Eichoff) (RAB) (Coleoptera: Curculionidae). LWD has caused tree mortality throughout the southeastern United States and is continuing to spread into new regions. Current management methods have not been successful in preventing spread, warranting investigation into innovative techniques including RNA interference (RNAi).

Elongation factor-1 alpha (ef1a) and actin (act) were established as stably expressed reference genes after exposing beetles to different photoperiod, temperature, and dsRNA exposure. After RAB oral …

Regulation Of Erk3 By Kras Signalling And Its Role In The Growth Of Lung Adenocarcinoma (Luad) Cells, Shreya Akunapuram

Browse all Theses and Dissertations

Extracellular signal related kinase 3 (ERK3) is one of the atypical mitogen activated protein kinases (MAPK). It is expressed ubiquitously and plays a role in a variety of cellular processes, including cell growth and differentiation. ERK3’s role in promoting migration and invasion in various cancers has been well established. ERK3 is upregulated in non-small cell lung cancers (NSCLCs) and has been shown to promote NSCLC tumor growth and progression. However, the regulation of ERK3 in lung cancers remains largely unclear. A recent study indicates that ERK3 phosphorylation at S189, an indicator of ERK3 activity, is upregulated by KRAS in NSCLCs. …

Dna Methylation And The Response To Infection In Introduced House Sparrows, Melanie Gibson

College of Graduate Studies: Theses & Dissertations

Epigenetics is the study of molecular modification of a genome without changing its base pairs. The most studied type of epigenetic mechanism is DNA methylation, which is capable of turning a gene “on” or “off.” Epigenetic potential is the capacity to which an individual can have methylation on its genome. The more CpGs available, the greater the epigenetic potential. In invasive species, genetic variation has been observed to be paradoxical: not much of it exists on a genomic level, but epigenetically, phenotypic variation can occur. The focus on shift in gene expression in this study is on Toll-Like Receptor 4 …

Structure–Activity Relationship Studies On 6-Chloro-1-Phenylbenzazepines Leads To The Identification Of A New Dopamine D1 Receptor Antagonist, Rajan Giri, Hari K. Namballa, Vishwashiv Emogaje, Wayne W. Harding

Publications and Research

The 1-phenylbenzazepine template has yielded a number of D1R-like ligands, which, though useful as pharmacological tools, have significant drawbacks in terms of selectivity versus D5R as well as pharmacokinetic behavior. A number of 1-phenylbenzazepines contain a 6-chloro functional group, but extensive SAR studies around the 6-chloro-1-phenylbenzazepine framework have not been reported in the literature. To further understand the tolerance of the 6-chloro-1-phenylbenzazepine template for various substituent groups towards affinity and selectivity at D1R, we synthesized two series of analogs with structural variations at the C-7, C-8, N-3, C-3′ and C-4′ positions. The series 2 analogs differed from …

Effects Of Depth, Distance To Shore, And Water Velocity On Organismal And Extra-Organismal Environmental Dna Concentrations In A Large River, Dylan Keel

Cal Poly Humboldt theses and projects

Environmental DNA (eDNA) is a sensitive tool for detection of aquatic species and concentrations of eDNA in water samples have been useful for estimating abundance. This study evaluated the effects of depth, distance to shore, and water velocity on the concentration of organismal and extra-organismal eDNA concentrations in the Klamath River, California (basin area ≅ 40,000 km²). At each of six river cross sections 32 water samples were collected, including surface samples and depth samples evenly distributed across the cross section, and eDNA concentrations were determined for the parasite Ceratonova shasta and Chinook salmon, Oncorhynchus tshawytscha, using …

Plastic Recognition And Electrogenic Uniport Translocation Of 1st-, 2nd-, And 3rd-Row Transition And Post-Transition Metals By Primary-Active Transmembrane P1b-2-Type Atpase Pumps, Sameera S. Abeyrathna, Nisansala S. Abeyrathna, Priyanka Basak, Gordon W. Irvine, Limei Zhang, Gabriele Meloni

Department of Biochemistry: Faculty Publications

Transmembrane P-type ATPase pumps catalyze the extrusion of transition metal ions across cellular lipid membranes to maintain essential cellular metal homeostasis and detoxify toxic metals. Zn()-pumps of the P-type subclass, in addition to Zn , select diverse metals (Pb, Cdand Hg) at their transmembrane binding site and feature promiscuous metal-dependent ATP hydrolysis in the presence of these metals. Yet, a comprehensive understanding of the transport of these metals, their relative translocation rates, and transport mechanism remain elusive. We developed a platform for the characterization of primary-active Zn()-pumps in proteoliposomes to study metal selectivity, translocation events and transport mechanism in real-time, …

The Role Of Myocardin In The Progression Of Non-Small Cell Lung Cancer, Soromidayo Akinsiku

Biotechnology Theses

Lung cancer is the leading cause of cancer-related mortality in the world and NSCLC accounts for 85% of all lung cancer cases. The mainstay of treatment for patients with stage I, II and IIIA NSCLC is surgery, followed by post-operative cisplatin-based chemotherapy. Additional adjuvant therapy involving targeted tyrosine kinase inhibitors has been in use, however even for the targeted therapy, resistance eventually develops. Therefore, there is a need for identifying novel targets for this life-threatening disease. Given that preliminary studies in Ikebe lab revealed that myocardin knockdown significantly promoted caspase-3 degradation, in this study, using myocardin siRNA, we investigated the …

การเกิดภาวะพหุสัณฐานทางพันธุกรรมของยีนในวิถีวิตามินดีและความเสี่ยงต่อภาวะออทิซึมสเปกตรัมในประชากรไทย, ชาญณรงค์ แซ่ฉั่ว

Chulalongkorn University Theses and Dissertations (Chula ETD)

กลุ่มอาการออทิซึมสเปกตรัม (Autism spectrum disorder; ASD) เป็นปัญหาสุขภาพระดับโลกที่สำคัญ โดยพบว่ามีความชุกของโรคที่เพิ่มสูงขึ้น อย่างไรก็ตามสาเหตุและกลไกในการเกิดภาวะออทิซึมสเปกตรัมยังไม่ทราบแน่ชัดอาจเกี่ยวข้องกับปัจจัยด้านพันธุกรรมและสิ่งแวดล้อม โดยปัจจุบันมีรายงานถึงบทบาทของวิตามินกับภาวะออทิซึมสเปกตรัม วัตถุประสงค์ของการศึกษานี้คือศึกษาการเกิดภาวะพหุสัณฐานทางพันธุกรรมของยีนในวิถีเมทาบอลิกของวิตามินดีและความเสี่ยงต่อการเกิดภาวะออทิซึมสเปกตรัมและระดับความรุนแรงของโรคในเด็กไทย การศึกษานี้มีจำนวนอาสาสมัคร 276 ราย โดยเป็นกลุ่มเด็กที่มีภาวะออทิซึมสเปกตรัม 169 ราย และกลุ่มควบคุมเป็นเด็กที่ไม่มีโรคทางระบบประสาท 107 ราย ซึ่งได้ทำการตรวจวิเคราะห์ภาวะพหุสัณฐานทางพันธุกรรมของยีน CYP2R1, CYP27B1, GC และ VDR โดยเทคนิค TaqMan-based real-time Polymerase Chain Reaction (PCR) และตรวจวิเคราะห์ระดับวิตามินดีในกระแสเลือดโดยใช้เทคนิค Chemiluminescence Immunoassay (CLIA) โดยเด็กที่พบภาวะออทิซึมสเปกตรัมจะได้รับการตรวจระดับความรุนแรงของภาวะออทิซึมสเปกตรัมด้วย Childhood Autism Rating Scale, 2nd Edition (CARS2) โดยผลที่ได้จากการศึกษาพบว่า การเกิดภาวะพหุสัณฐานทางพันธุกรรมของยีน CYP2R1, CYP27B1, VDR และ GC (rs4588) ไม่มีความสัมพันธ์กับการเกิดภาวะออทิซึมสเปกตรัมและความรุนแรงของอาการออทิซึมสเปกตรัม อย่างไรก็ตามการศึกษาชี้ให้เห็นว่า การเกิดภาวะพหุสัณฐานทางพันธุกรรมของยีน GC (rs7041 (A>C)) มีความสัมพันธ์อย่างมีนัยสำคัญกับความเสี่ยงที่เพิ่มขึ้นต่อการเกิดภาวะออทิซึมสเปกตรัมและความรุนแรงของอาการออทิซึมสเปกตรัมด้วย โดยเฉพาะอย่างยิ่งบุคคลที่มีการขาดระดับวิตามินดีร่วมด้วย นอกจากนี้ผลศึกษาพบว่าไอโซฟอร์มของ GC1s และ GC1s-GC1s ฟีโนไทป์มีความสัมพันธ์อย่างมีนัยสำคัญกับความเสี่ยงต่อการเกิดภาวะออทิซึมสเปกตรัมตลอดจนความรุนแรงของอาการออทิซึมสเปกตรัม โดยสรุปการศึกษาวิจัยในครั้งนี้ชี้ให้เห็นว่า การเกิดภาวะพหุสัณฐานทางพันธุกรรมของยีน GC (rs7041 (A>C)) และไอโซฟอร์ม GC1s อาจเป็นตัวบ่งชี้ทางพันธุกรรมที่สามารถช่วยในการประเมินความเสี่ยงต่อการเกิดภาวะออทิซึมสเปกตรัมและความรุนแรงของอาการออทิซึมสเปกตรัมในเด็กไทยได้ในอนาคต อย่างไรก็ตามการศึกษาในอนาคตควรศึกษาในกลุ่มประชากรที่ใหญ่ขึ้นเพื่อยืนยันผลการศึกษาวิจัยครั้งนี้

Development And Biological Evaluation Of Selective Small-Molecule Inhibitors Of The Human Cytochrome P450 1b1, Austin Hachey

Theses and Dissertations--Chemistry

The human cytochrome P450 1B1 (CYP1B1) is an emerging target for small- molecule therapeutics. Several solid tumors overexpress CYP1B1 to the degree that it has been referred to as a universal tumor antigen. Conversely, its expression is low in healthy tissues. CYP1B1 may drive tumorigenesis through promoting the formation of reactive toxins from environmental pollutants or from endogenous hormone substrates. Additionally, the expression of CYP1B1 in tumors is associated with resistance to several common chemotherapies and with poor prognoses in cancer patients. However, inhibiting CYP1B1 with small molecules has been demonstrated in cellular and murine model systems to reverse this …

Characterization Of Parp1-Dependent Poly-Adp-Ribosylation Of Sprtn, Quincee Simonson

Electronic Theses and Dissertations

DNA-protein crosslinks (DPCs) are a type of DNA lesion that form when proteins become covalently linked to DNA. It is estimated that replicating cells experience approximately 6,000 DPCs per day per genome during exponential growth (Ruggiano & Ramadan, 2021). If left unrepaired, DPCs can be lethal to cells. For this reason, cells have evolved multiple pathways to repair or bypass DPCs to survive. One such pathway involves SPRTN, a nuclear metalloprotease that plays a key role in the repair of DPCs through direct proteolysis (Lopez-Mosqueda et al., 2016; Vaz et al., 2016). Once SPRTN degrades the bulky protein component of …

Modulatory Effects Of Deacetylated Sialic Acids (A Sugar Residue) In Nk-Mediated Cytotoxicity And Targeted Therapy By Receptor Tyrosine Kinase Inhibitors, Mathias Tawiah Anim

Electronic Theses and Dissertations

The complex nature of the biology of cancer is still an unraveling science, yielding several biomarkers that have served as molecular targets for detection and treatment of the disease. How sugars, glycans, play a role has remained relatively uninvestigated. Sialic acid (Sia), a sugar residue on the surface of cells, has been identified as a hallmark of cancer and its progression. Sialic acid can be highly functionalized, but we became interested in acetylated Sias. This functional group is modulated by Sialate O- acetylesterase (encoded by the gene SIAE) and Sialate O-acetyltransferase (encoded by CASD1), enzymes that play a crucial role …

Approaches To Avoid Proteolysis During Protein Expression And Purification, Gary T. Henehan, Barry J. Ryan, Gemma K. Kinsella

Books/Book Chapters/ Proceedings

All cells contain proteases, which hydrolyze the peptide bonds between amino acids of a protein backbone. Typically, proteases are prevented from nonspecific proteolysis by regulation and by their physical separation into different subcellular compartments; however, this segregation is not retained during cell lysis, which is the initial step in any protein isolation procedure. Prevention of proteolysis during protein purification often takes the form of a two-pronged approach: first, inhibition of proteolysis in situ, followed by the early separation of the protease from the protein of interest via chromatographic purification. Protease inhibitors are routinely used to limit the effect of the …

Structural And Spectroscopic Study Of New Copper(Ii) And Zinc(Ii) Complexes Of Coumarin Oxyacetate Ligands And Determination Of Their Antimicrobial Activity, Muhammad Mujahid, Natasha Trendafilova, Georgina Rosair, Kevin Kavanagh, Maureen Walsh, Bernadette Creaven, Ivelina Georgieva

Articles

Tackling antimicrobial resistance is of increasing concern in a post-pandemic world where overuse of antibiotics has increased the threat of another pandemic caused by antimicrobial-resistant pathogens. Derivatives of coumarins, a naturally occurring bioactive compound, and its metal complexes have proven therapeutic potential as antimicrobial agents and in this study a series of copper(II) and zinc(II) complexes of coumarin oxyacetate ligands were synthesised and characterised by spectroscopic techniques (IR, 1H, 13C NMR, UV-Vis) and by X-ray crystallography for two of the zinc complexes. The experimental spectroscopic data were then interpreted on the basis of molecular structure modelling and subsequent spectra simulation …

Identification Of Novel Biosynthetic Gene Clusters Encoding For Polyketide/Nrps-Producing Chemotherapeutic Compounds From Marine-Derived Streptomyces Hygroscopicus From A Marine Sanctuary, Hannah Ruth Flaherty

Honors Theses and Capstones

Nearly one out of six deaths in 2020, around ten million people, were caused by cancer, making it a leading cause of death worldwide (WHO, 2022). This major public health issue, in addition to the rise of multidrug-resistant (MDR) pathogens, provides a high demand for the discovery of new pharmaceutical drugs to be used clinically to treat these conditions. The Streptomyces genus accounts to produce 39% of all microbial metabolites currently approved for human health, indicating its potential as an important species to study for antimicrobial and anticancer agents. The long linear genome of Streptomyces contains specialized sequences known as …

Structural Files For The Etr1 Ethylene-Receptor Dimer Based On Computational Modeling, Beenish J. Azhar, Safdar Abbas, Sitwat Aman, Maria V. Yamburenko, Wei Chen, Lena Muller, Buket Uzun, David A. Jewell, Jian Dong, Samina N. Shakeel, Georg Groth, Brad M. Binder, Gevorg Grigoryan, G. Eric Schaller

Dartmouth Scholarship

Structural models for the ETR1 homodimer were generated with AlphaFold-Multimer. Coppers were modeled under two potential coordinations involving Cys65 and His69 of the ETR1 homodimer, one in which the two coppers are bound independently and do not share an interaction with each other, and another where they are closely bonded.

See the following publication for details: Azhar, B.J., Abbas, S., Aman, S., Yamburenko, M.V., Chen, W., Müller, L., Uzun, B., Jewell, D.A., Dong, J., Shakeel, S.N., Groth, G., Binder, B.M., Grigoryan, G., Schaller, G.E. (2023) Basis for high-affinity ethylene binding by the ethylene receptor ETR1 of Arabidopsis. Proc. Natl. Acad. …

Design Of Block Copolymer With Tunable Hydrophobic/Hydrophilic/Fluorophilic Interactions, Tatiane De Fatima Dutra

Theses, Dissertations and Culminating Projects

Block copolymers (BCP) with balanced interactions and their resultant bulk-phase self-assembly have become increasingly important in advancing nanotechnology, separation, and energy applications. However, a few reports have addressed the synthesis challenge and bulk-phase self-assembly of such triblock copolymers. This thesis presents a facile route for preparing triblock copolymer via controlled radical and organocatalytic ring-opening polymerization that allows precise control over the incorporation of individual moieties in resultant polymer, responsible for balanced hydrophilic, hydrophobic/lipophilic, and fluorophilic interactions. Synthesized polymer with suggested self-assembled 2D lamellar nanostructure exhibits high-temperature stability. The long-term goal of this work is to selectively use this polymer class …

A Computational Study Of The Copper-Catalyzed Trifluoromethylation Of Boronic Acids, Kevin Nyhuis

Theses, Dissertations and Culminating Projects

This work is a computational study of a reaction mechanism for the trifluoromethylation of boronic acids. Three steps of the proposed reaction mechanism are studied, •CF₃ addition to a copper catalyst center, base promoted transmetalation between copper and aryl boronic acid, and bond forming reductive elimination in which the CF₃ and aryl substituent form a bond. Limited information is known about this mechanism. This study uses computational methods to attempt to elucidate the mechanism and provide the groundwork for potential improvement. Quantum chemical methods in conjunction with tight-binding based conformational sampling methods are used to investigate the possible …

Investigating The Roles Of Active Site Residues K59, K119 And E168 In M. Tuberculosis Indole-3-Glycerol Phosphate Synthase, Maryum M. Bhatti

Theses, Dissertations and Culminating Projects

Tuberculosis (TB) is a disease that is caused by a bacteria called Mycobacterium tuberculosis and primarily attacks the lungs but can spread to other areas of the body as well. TB can develop resistance to drugs that may be used to cure the disease. Multidrug resistant TB is especially a growing issue as it does not respond to the two most powerful anti-TB drugs, isoniazid and rifampicin. For this reason, finding new ways to target TB are critically needed. One possible way to do this is to target the enzymes in the tryptophan biosynthetic pathway of M. tuberculosis. Studies have …

Presumptive Hepatogenous Photosensitization In Beef Cattle Winter Grazing A Cover Crop Containing Brassica Spp. Turnips, Matthew M. Hille, Scott A. Fritz, Breanna C. Brown

School of Veterinary and Biomedical Sciences: Faculty Publications

Over a period of ~2 wk, 5 adult beef cows developed severe necrotizing skin lesions on the face and neck shortly after being moved to a field with a cover crop of Brassica spp. turnips. We describe here the clinical signs, hematology, and serum chemistry results, as well as gross and histopathologic findings, from this outbreak. We made a presumptive diagnosis of Brassica-associated liver disease (BALD) based on the similarities in the history and diagnostic findings observed with previously reported cases of BALD from elsewhere in the world. BALD has not been reported previously in cattle in North America, …

Arginine-178 Is An Essential Residue For Itpa Function, Nicholas E. Burgis, Caitlin April, Kandise Vanwormer

Chemistry and Biochemistry Faculty Publications

The inosine triphosphate pyrophosphatase (ITPA) enzyme plays a critical cellular role by removing noncanonical nucleoside triphosphates from nucleotide pools. One of the first pathological ITPA mutants identified is R178C (rs746930990), which causes a fatal infantile encephalopathy, termed developmental and epileptic encephalopathy 35 (DEE 35). The accumulation of noncanonical nucleotides such as inosine triphosphate (ITP), is suspected to affect RNA and/or interfere with normal nucleotide function, leading to development of DEE 35. Molecular dynamics simulations have shown that the very rare R178C mutation does not significantly perturb the overall structure of the protein, but results in a high level of structural …