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Articles 1111 - 1140 of 13230

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

The Role Of The Circadian Clock In Disease And Tissue Function, Marvin Wirianto Aug 2024

The Role Of The Circadian Clock In Disease And Tissue Function, Marvin Wirianto

Dissertations and Theses (Open Access)

The mammalian circadian clock responds to the 24-hour daily cycle and regulates tissue-specific gene expression and downstream physiology. The central pacemaker located in the hypothalamic suprachiasmatic nuclei (SCN) synchronizes the peripheral clocks in different tissues. This dissertation aims to uncover specific circadian regulatory mechanisms in the brain and skeletal muscle.

Alzheimer’s Disease (AD) is the most common type of dementia. It has previously been shown that there is a strong correlation of disease progression with circadian rhythm decline. We showed that circadian modulation by a small molecule Nobiletin (NOB) was able to mitigate AD pathogenesis. Furthermore, NOB significantly alleviated the …


Exploring Acetate Metabolism: Genetically Characterizing Acetate Production And Acetate Utilization In The Fungal Pathogen Cryptococcus Neoformans, Rodrigo Catalan-Hurtado Aug 2024

Exploring Acetate Metabolism: Genetically Characterizing Acetate Production And Acetate Utilization In The Fungal Pathogen Cryptococcus Neoformans, Rodrigo Catalan-Hurtado

All Dissertations

The basidiomycete Cryptococcus neoformans is an invasive opportunistic fungal pathogen and the most frequent cause of fungal meningitis resulting in approximately 112,000 deaths per year worldwide. Recently, the World Health Organization systematically prioritized fungal pathogens in which C. neoformans was among four fungal pathogens deemed critically important. Current methods of treatment are inadequate for most of the infected population; therefore, it is imperative to find novel therapeutic targets. Previous studies have shown that acetate is a major metabolite found in biopsies of C. neoformans infected mouse brain and lung tissues. Two potential pathways for acetate production have been identified. …


Assessment Of Tce And Chiral Pcb Dechlorination Rate, Congener Diversity, And Enantioselectivity In Town Creek, Sc, Usa Sediment Microcosms, Catherine P. Sumner Aug 2024

Assessment Of Tce And Chiral Pcb Dechlorination Rate, Congener Diversity, And Enantioselectivity In Town Creek, Sc, Usa Sediment Microcosms, Catherine P. Sumner

All Dissertations

Polychlorinated biphenyls (PCBs) and trichloroethene (TCE) are ubiquitous contaminants and are recognized as persistent organic pollutants due to their extreme chemical stability. PCBs were manufactured by chlorinating biphenyls that created 209 congeners with various structures, of which 19 are chiral and can exist as a pair of stable atropisomers. PCBs have been known to cause developmental and neurological toxicity in humans and wildlife; they can act as endocrine disrupters, carcinogens, and teratogens. Sangamo Weston Inc. was an industrial plant located near Town Creek in Pickens Country, South Carolina, that manufactured capacitors and used Aroclors 1016 and 1254 as dialectic fluids …


Candida Albicans Farnesol Synthesis And Secretion, Daniel J. Gutzmann Aug 2024

Candida Albicans Farnesol Synthesis And Secretion, Daniel J. Gutzmann

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

Candida albicans is a polymorphic fungus and opportunistic commensal found primarily in the gastrointestinal and skin of healthy individuals. Several barriers prevent C. albicans from causing disease including a healthy immune system and microbiome. When these barriers become comprised, C. albicans can transition to a pathogen and disseminate through the intestinal mucosa leading to life-threatening bloodstream and invasive infections with mortality rates of up to 64%. Morphogenic plasticity is key to this transition and impacts virulence, adaptation to different host environments, and evasion of host immune responses. One regulator of morphogenesis is farnesol. Farnesol is a secondary metabolite of …


Synergistic Effects Of Novel Penicillin-Binding Protein 1a Amino Acid Substitutions Contribute To High-Level Amoxicillin Resistance Of Helicobacter Pylori, Alain Cimuanga-Mukanya, Evariste Tshibangu-Kabamba, Patrick De Jesus Ngoma Kisoko, Fabien Mbaya Tshibangu, Antoine Tshimpi Wola, Pascal Tshiamala Kashala, Dieudonné Mumba Ngoyi, Steve Ahuka-Mundeke, Gunturu Revathi, Ghislain Disashi-Tumba Aug 2024

Synergistic Effects Of Novel Penicillin-Binding Protein 1a Amino Acid Substitutions Contribute To High-Level Amoxicillin Resistance Of Helicobacter Pylori, Alain Cimuanga-Mukanya, Evariste Tshibangu-Kabamba, Patrick De Jesus Ngoma Kisoko, Fabien Mbaya Tshibangu, Antoine Tshimpi Wola, Pascal Tshiamala Kashala, Dieudonné Mumba Ngoyi, Steve Ahuka-Mundeke, Gunturu Revathi, Ghislain Disashi-Tumba

Pathology, East Africa

The growing resistance to amoxicillin (AMX)—one of the main antibiotics used in Helicobacter pylori eradication therapy—is an increasing health concern. Several mutations of penicillin-binding protein 1A (PBP1A) are suspected of causing AMX resistance; however, only a limited set of these mutations have been experimentally explored. This study aimed to investigate four PBP1A mutations (i.e., T558S, N562H, T593A, and G595S) carried by strain KIN76, a high-level AMX-resistant clinical H. pylori isolate with an AMX minimal inhibition concentration (MIC) of 2 µg/mL. We transformed a recipient strain 26695 with the DNA containing one to four mutation allele combinations of the pbp1 gene …


Unraveling The Complex Dynamics Of Cardiac Fibrosis: Ccn1 As A Novel Regulator Of Scar Collagen Architecture And Structural Integrity In Myocardial Infarction., Annalara Garland Fischer Aug 2024

Unraveling The Complex Dynamics Of Cardiac Fibrosis: Ccn1 As A Novel Regulator Of Scar Collagen Architecture And Structural Integrity In Myocardial Infarction., Annalara Garland Fischer

Electronic Theses and Dissertations

Expansion of the extracellular matrix (ECM), known as fibrosis, accompanies nearly all forms of cardiac disease; however, its most significant and complex manifestations arise following a myocardial infarction (MI). This process, principally led by fibroblasts, constitutes a necessary and adaptive response acutely to fill the void from cardiomyocyte necrosis following ischemic injury due to the heart’s lack of regenerative capacity. This acute response never fully resolves and contributes to ongoing collagen accumulation in non-infarcted regions, leading to diminished ventricular compliance, ongoing myocyte loss, and attrition in function—culminating in heart failure. Further, recent research demonstrates that concomitant with progressive increases in …


L-Arabinose Induced Overexpression For Crystallographic Analysis Of The Spoiie Protein From Clostridioides Difficile, Danielle M. Maynard Aug 2024

L-Arabinose Induced Overexpression For Crystallographic Analysis Of The Spoiie Protein From Clostridioides Difficile, Danielle M. Maynard

Graduate Theses and Dissertations

The SpoIIE protein plays a crucial role in the sporulation process of Clostridioides difficile, a pathogen responsible for severe gastrointestinal diseases. Understanding the structural and functional aspects of SpoIIE is pivotal for deciphering its role in sporulation and exploring its potential as a therapeutic target. This study investigates the impact of varying concentrations of L-arabinose on the overexpression of SpoIIE in C. difficile, aiming to optimize protein yield and purity for subsequent crystallization and structural determination via X-ray crystallography. Using a recombinant expression system in Escherichia coli, different concentrations of L-arabinose were employed to induce SpoIIE overexpression. Protein purification was …


Metal Assisted O2-Dependent Carbon-Carbon Bond Cleavage Of Β-Diketones And Flavonols, Stephen N. Anderson Aug 2024

Metal Assisted O2-Dependent Carbon-Carbon Bond Cleavage Of Β-Diketones And Flavonols, Stephen N. Anderson

All Graduate Theses and Dissertations, Fall 2023 to Present

Almost everything we interact with on a daily basis has been synthesized by chemists ranging from plastics, food preservatives, and medications. The diversity of synthetic molecules are achieved by the formation of new bonds between existing molecules and/or through the cleaving of bonds found in a molecule. There are uncountable amount of conditions reported to facilitate chemical reactions which all depend on the nature of molecules being used and the environment it is used in.

In recent years, more attention has been paid to identify chemical reactions that can use more environmentally favorable conditions and reduce the use of limited …


Documenting The Spatial And Temporal Dynamics Of Pair-Rule Genes In The Early Tribolium Embryo, Hasan Mahmud Aug 2024

Documenting The Spatial And Temporal Dynamics Of Pair-Rule Genes In The Early Tribolium Embryo, Hasan Mahmud

Theses and Dissertations

Although Insects and vertebrates have different anatomical structures, they possess similar mechanisms for segmenting during embryogenesis. Clock and wavefront model exhibit a similar pattern of division as observed in Drosophila, like vertebrates, which emphasizes fundamental principles in the field of developmental biology. In contrast to Drosophila, the insect Tribolium castaneum exhibits posterior segmentation originating from the growth zone. The pair-rule genes’ expression is characterized by oscillatory patterns, which are controlled by a segmentation clock. Researchers found that the speed regulation model combines oscillatory and sequential gene activities to shape both elongating and non-elongating embryonic tissues. The adaptability of this model …


Diatom Abundance In The Polar Oceans Is Predicted By Genome Size, Wade R. Roberts, Adam M. Siepielski, Andrew J. Alverson Aug 2024

Diatom Abundance In The Polar Oceans Is Predicted By Genome Size, Wade R. Roberts, Adam M. Siepielski, Andrew J. Alverson

Biological Sciences Faculty Publications and Presentations

A principal goal in ecology is to identify the determinants of species abundances in nature. Body size has emerged as a fundamental and repeatable predictor of abundance, with smaller organisms occurring in greater numbers than larger ones. A biogeographic component, known as Bergmann’s rule, describes the preponderance, across taxonomic groups, of larger-bodied organisms in colder areas. Although undeniably important, the extent to which body size is the key trait underlying these patterns is unclear. We explored these questions in diatoms, unicellular algae of global importance for their roles in carbon fixation and energy flow through marine food webs. Using a …


Diapause Specific Proteins Of A Brine Shrimp Form Liquid Droplets Dependent On Salt And Ph Levels, Kolby Sanders, Alex Haydon, Charles Elder, David Grimm, Michael Menze Jul 2024

Diapause Specific Proteins Of A Brine Shrimp Form Liquid Droplets Dependent On Salt And Ph Levels, Kolby Sanders, Alex Haydon, Charles Elder, David Grimm, Michael Menze

Undergraduate Research Events

Liquid-Liquid Phase Separation (LLPS) is a process when a polypeptide condenses into a dense and dilute phase in aqueous solutions. Within cells, this process is believed to relate to stress regulation and various cellular processes. Several stress-related proteins found only during the embryonic developmental stage of diapause in the brine shrimp, A. franciscana, have been observed to undergo LLPS in vitro. Our results show that the small heat shock protein (sHSP) p26 has a greater propensity to LLPS under varying salt concentrations compared to LEA6, a late embryogenesis abundant protein (LEA). At a protein concentration of 1.31 mg/ml in …


Computational Modelling And Design Of Antibodies: Benefits From Analysis Of Their Unique Structural Motifs, Katherine M. Mccoy Jul 2024

Computational Modelling And Design Of Antibodies: Benefits From Analysis Of Their Unique Structural Motifs, Katherine M. Mccoy

Dartmouth College Ph.D Dissertations

The complexes that antibodies make with their binding partners, or antigens, are especially valuable to be able to predict and modify due to their unique role in the immune system. Yet, they present significant challenges to computational methods of both modelling and design. Antibodies are unlike most other proteins in that they are composed of a scaffold region, which is a highly conserved structure that is largely the same between antibodies of the same class, and Complementary Determining Regions (CDRs), which are comprised of hypervariable loops that largely determine their binding motifs. Additionally, antibodies and their antigens do not co-evolve …


Elevating Plk1 Overcomes Beti Resistance In Prostate Cancer Via Triggering Brd4 Phosphorylation-Dependent Degradation In Mitosis, Yanquan Zhang, Ka-Wing Fong, Fengyi Mao, Ruixin Wang, Derek B. Allison, Dana Napier, Daheng He, Jinpeng Liu, Yeqing Zhang, Jing Chen, Yifan Kong, Chaohao Li, Guangbing Li, Jinghui Liu, Zhiguo Li, Haining Zhu, Chi Wang, Xiaoqi Liu Jul 2024

Elevating Plk1 Overcomes Beti Resistance In Prostate Cancer Via Triggering Brd4 Phosphorylation-Dependent Degradation In Mitosis, Yanquan Zhang, Ka-Wing Fong, Fengyi Mao, Ruixin Wang, Derek B. Allison, Dana Napier, Daheng He, Jinpeng Liu, Yeqing Zhang, Jing Chen, Yifan Kong, Chaohao Li, Guangbing Li, Jinghui Liu, Zhiguo Li, Haining Zhu, Chi Wang, Xiaoqi Liu

Markey Cancer Center Faculty Publications

Bromodomain-containing protein 4 (BRD4) has emerged as a promising therapeutic target in prostate cancer (PCa). Understanding the mechanisms of BRD4 stability could enhance the clinical response to BRD4-tar- geted therapy. In this study, we report that BRD4 protein levels are significantly decreased during mitosis in a PLK1-dependent manner. Mechanistically, we show that BRD4 is primarily phosphorylated at T1186 by the CDK1/cyclin B complex, recruiting PLK1 to phosphorylate BRD4 at S24/S1100, which are recognized by the APC/CCdh1 complex for proteasome pathway degradation. We find that PLK1 overexpression lowers SPOP mutation-stabilized BRD4, consequently rendering PCa cells re-sensitized to BRD4 inhibitors. Intrigu-ingly, we …


Defining A Dynamic Architecture Of Protein Tyrosine Phosphatases, Colin L. Welsh Jul 2024

Defining A Dynamic Architecture Of Protein Tyrosine Phosphatases, Colin L. Welsh

MUSC Theses and Dissertations

Protein tyrosine phosphatases (PTPs), a critical class of signaling enzymes, are principally responsible for balancing the actions of kinases through the dephosphorylation of tyrosine residues on substrate proteins. As such, this family is involved in myriad pathways and individual members are able to perform both oncogenic and tumor-suppressing roles. However, while clinical success has been achieved in targeting kinases, PTPs have remained therapeutically challenging. Orthosteric inhibition is limited in PTPs due to their highly conserved fold, leading to off-target effects, and their highly charged active site, requiring highly polar molecules with poor bioavailability. These challenges posit the allosteric inhibition of …


Exploring Chilling Stress And Recovery Dynamics In C4 Perennial Grass Of Miscanthus Sinensis, Karolina Sobańska, Monika Mokrzycka, Martyna Przewoźnik, Tomasz Pniewski, Katarzyna Glowacka Jul 2024

Exploring Chilling Stress And Recovery Dynamics In C4 Perennial Grass Of Miscanthus Sinensis, Karolina Sobańska, Monika Mokrzycka, Martyna Przewoźnik, Tomasz Pniewski, Katarzyna Glowacka

Department of Biochemistry: Faculty Publications

The increasing cultivation of perennial C4 grass known as Miscanthus spp. for biomass production holds promise as a sustainable source of renewable energy. Unlike the sterile triploid hybrid of M. × giganteus, which cannot reproduce through seeds, M. sinensis possesses attributes that could potentially address these limitations by effectively establishing itself through seed propagation. This study aimed to investigate how 18 genotypes of M. sinensis respond to chilling stress and subsequent recovery. Various traits were measured, including growth and biomass yield, the rate of leaf elongation, and a variety of chlorophyll fluorescence parameters, as well as chlorophyll …


Mutant Androgen Receptor Induces Neurite Loss And Senescence Independently Of Are Binding In A Neuronal Model Of Sbma, Jordyn Karliner, Y Liu, Diane Merry Jul 2024

Mutant Androgen Receptor Induces Neurite Loss And Senescence Independently Of Are Binding In A Neuronal Model Of Sbma, Jordyn Karliner, Y Liu, Diane Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Spinal and bulbar muscular atrophy (SBMA) is a slowly progressing neuromuscular disease caused by a polyglutamine (polyQ)-encoding CAG trinucleotide repeat expansion in the androgen receptor (AR) gene, leading to AR aggregation, lower motor neuron death, and muscle atrophy. AR is a ligand-activated transcription factor that regulates neuronal architecture and promotes axon regeneration; however, whether AR transcriptional functions contribute to disease pathogenesis is not fully understood. Using a differentiated PC12 cell model of SBMA, we identified dysfunction of polyQ-expanded AR in its regulation of neurite growth and maintenance. Specifically, we found that in the presence of androgens, polyQ-expanded AR inhibited neurite …


Role Of Sds-22/Pp1 Phosphatase In Polarizing The Germplasm Of Caenorhabditis Elegans Embryo, Aparna Nurni Ravi Jul 2024

Role Of Sds-22/Pp1 Phosphatase In Polarizing The Germplasm Of Caenorhabditis Elegans Embryo, Aparna Nurni Ravi

Dartmouth College Ph.D Dissertations

During asymmetric cell division, cell polarity and cell cycle are tightly coupled to ensure robust segregation of cell fate determinants and generation of cellular diversity. In the one-cell C. elegans embryo, multiple cell cycle kinases regulate cell polarization and posterior segregation of germline fate determinants (germplasm). For example, PLK-1 kinase inhibits the retention of its germplasm substrate POS-1 in the anterior, driving POS-1 segregation to the posterior (Han et al., 2018). Additionally, MBK-2 kinase disassembles P granules in the anterior through phosphorylation of the P granule scaffold MEG-3, helping to drive P granule segregation to the posterior (Wang et al., …


Functional And Structural Analysis Of The Neimann-Pick Disease Type C Pathway To Include Caveolin-1, Anthony Michael Seat Jul 2024

Functional And Structural Analysis Of The Neimann-Pick Disease Type C Pathway To Include Caveolin-1, Anthony Michael Seat

Chemistry and Chemical Biology ETDs

Human disease is often thought of as an all or nothing prospect, either one has the disease or one does not. This does not bear out in clinical or personal experiences, instead demonstrating that disease occurs within a spectrum ranging from presumed unaffected to demonstrably and detrimentally affected.Neimann-Pick disease is one example of this spectrum look into diseased states, with multiple named versions of a phenotypically similar disease. We focus on Neimann-Picktype C (NPC), which is the result of a disruption in the efflux of cholesterol and sphingolipids from the endocytic pathway. NPC demonstrates this concept of a spectrum of …


Conformational Alterations Of The Cell Surface Of Monomeric And Dimeric Β2m-Free Hla-I (Proto-Hla) May Enable Novel Immune Functions In Health And Disease, Mepur Ravindranath, Narendranath Ravindranath, Carly Amato-Menker, Fatiha El Hilali, Edward Filippone Jul 2024

Conformational Alterations Of The Cell Surface Of Monomeric And Dimeric Β2m-Free Hla-I (Proto-Hla) May Enable Novel Immune Functions In Health And Disease, Mepur Ravindranath, Narendranath Ravindranath, Carly Amato-Menker, Fatiha El Hilali, Edward Filippone

Division of Nephrology Faculty Papers

Human leukocyte antigens (HLAs) are polymorphic glycoproteins expressed on the cell surface of nucleated cells and consist of two classes, HLA class I and HLA class II. In contrast, in mice, these molecules, known as H-2, are expressed on both nucleated cells and erythrocytes. HLA-I molecules (Face-1) are heterodimers consisting of a polypeptide heavy chain (HC) and a light chain, B2-microglobulin (B2m). The heterodimers bind to antigenic peptides and present them to the T-cell receptors of CD8+ cytotoxic T lymphocytes. The HCs can also independently emerge on the cell surface as B2m-free HC monomers without peptides (Face-2). Early investigators suggested …


Wee1 And Cell Size Control In Fission Yeast By The Protein Kinase Cdr2, Rachel Berg-Murante Jul 2024

Wee1 And Cell Size Control In Fission Yeast By The Protein Kinase Cdr2, Rachel Berg-Murante

Dartmouth College Ph.D Dissertations

The mechanisms that govern cell size have long been topics of study in the field of cell biology. In eukaryotic cells this size control is tied to checkpoints, a set threshold of minimum necessary growth linked to cyclin dependent kinase activity regulation. In the fission yeast Schizosaccharomyces pombe, the Cdk1 regulatory network is conserved, and G2/M represents the major size checkpoint. Prior to mitosis, Cdk1 is inhibited by phosphorylation applied by Wee1 during G2 phase. Once S. pombe cells have satisfied the size checkpoint, Cdk1 is activated through dephosphorylation by Cdc25. Wee1 is a dose-dependent regulator of mitotic entry …


Identifying The Relative Abundance Of Cell-Cell Signaling Peptides During Mammalian Hibernation And Anesthetic Administration By Label-Free Peptidomics Analysis, Somayeh Mousavi Jul 2024

Identifying The Relative Abundance Of Cell-Cell Signaling Peptides During Mammalian Hibernation And Anesthetic Administration By Label-Free Peptidomics Analysis, Somayeh Mousavi

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Cell-cell signaling molecules known as neuropeptide and peptide hormones, distributed in both the central nervous system (CNS) and the peripheral nervous system (PNS), regulate a variety of physiological processes including body temperature, feeding, circadian rhythm, reproduction, energy homeostasis, and more. While a number of active neuropeptides structures with physiological functions have been discovered, advances in peptidomic mass spectrometry are enabling researchers to uncover novel, previously unknown, active neuropeptide structures with potential for bioactivities. Using liquid chromatography coupled with tandem mass spectrometry (MS/MS), it is possible to identify a wide range of neuropeptides in single experiments without preselecting specific peptides. Mass …


Interleukin 24 Induces Apoptosis Through Glycogen Synthase Kinase-3 Beta Inactivation In Prostate Cancer Cells, Sual J. Lopez, Moira Sauane Jul 2024

Interleukin 24 Induces Apoptosis Through Glycogen Synthase Kinase-3 Beta Inactivation In Prostate Cancer Cells, Sual J. Lopez, Moira Sauane

Theses and Dissertations

Interleukin 24 (IL-24) is a tumor-suppressing protein currently in clinical trials. IL-24 induces cancer-specific apoptosis by activating endoplasmic reticulum (ER) stress and mitochondria dysfunction. We have previously demonstrated that IL-24 leads to apoptosis in cancer cells by protein kinase A (PKA) activation in human breast cancer cells. To further understand the mechanism by which IL-24 induces apoptosis, I analyzed the role of glycogen synthase kinase-3 (GSK3), a highly conserved and normally active serine/threonine kinase in cancer cells and downstream target of PKA. The work reported here provides direct evidence that GSK3 was inhibited following IL-24 treatment in human prostate cancer …


Identifying And Training Deep Learning Neural Networks On Biomedical-Related Datasets, Alan E. Woessner, Usman Anjum, Hadi Salman, Jacob Lear, Jeffrey T. Turner, Ross Campbell, Laura Beaudry, Justin Zhan, Lawrence E. Cornett, Susan Gauch, Kyle P. Quinn Jul 2024

Identifying And Training Deep Learning Neural Networks On Biomedical-Related Datasets, Alan E. Woessner, Usman Anjum, Hadi Salman, Jacob Lear, Jeffrey T. Turner, Ross Campbell, Laura Beaudry, Justin Zhan, Lawrence E. Cornett, Susan Gauch, Kyle P. Quinn

Computer Science and Computer Engineering Faculty Publications and Presentations

This manuscript describes the development of a resources module that is part of a learning platform named 'NIGMS Sandbox for Cloud-based Learning' https://github.com/NIGMS/NIGMS-Sandbox. The overall genesis of the Sandbox is described in the editorial NIGMS Sandbox at the beginning of this Supplement. This module delivers learning materials on implementing deep learning algorithms for biomedical image data in an interactive format that uses appropriate cloud resources for data access and analyses. Biomedical-related datasets are widely used in both research and clinical settings, but the ability for professionally trained clinicians and researchers to interpret datasets becomes difficult as the size and …


Structural Analysis Of Dj-1 Glyoxalase Activity By Mix-And-Inject Serial Synchrotron Crystallography, Coleman Dolamore Jul 2024

Structural Analysis Of Dj-1 Glyoxalase Activity By Mix-And-Inject Serial Synchrotron Crystallography, Coleman Dolamore

Department of Biochemistry: Dissertations, Theses, and Student Research

Observing enzyme structures while they are catalyzing a reaction has been a major goal of both enzymology and structural biology for decades. With the advent of time-resolved serial X-ray crystallography using X-ray free electron lasers (XFELs) and synchrotron sources, enzyme reactions can be monitored in real time in crystallo. Here, we use two different approaches to study related enzymes involved in methylglyoxal detoxification. For human DJ-1, we used pink beam mix-and-inject serial crystallography (MISC) at the Advanced Photon Source (BioCARS 14-ID) to probe the controversial mechanism of DJ-1’s action on methylglyoxal by using serial Laue diffraction. The high flux …


Study Of Atypical Alarmone Synthesis In Clostridioides Difficile, Declan Nathaniel Butler Jul 2024

Study Of Atypical Alarmone Synthesis In Clostridioides Difficile, Declan Nathaniel Butler

Chemistry & Biochemistry Theses & Dissertations

Clostridioides difficile is a Gram-positive anaerobic bacterium that causes infections in humans that costs healthcare systems billions per year. C. difficile infection has high rates of recurrence due to multiple antibiotic resistance. When bacteria are in stressful environments, they produce hyperphosphorylated guanosine ribonucleotide signaling molecules called alarmones. The accumulation of alarmones activates the stringent response (SR), in which bacterial cells induce transcription of stress survival genes to delay growth and replication. The C. difficile SR is regulated by enzymatic activity of a bifunctional synthetase/hydrolase, RelA/SpoT homolog (RSH), and a monofunctional small alarmone synthetase (RelQ). Additionally, the SR is potentially regulated …


Soxb1 Transcription Factors Are Essential For Initiating And Maintaining Neural Plate Border Gene Expression, Elizabeth Schock, Joshua R. York, Austin P. Li, Ashlyn Y. Tu, Carole Labonne Jul 2024

Soxb1 Transcription Factors Are Essential For Initiating And Maintaining Neural Plate Border Gene Expression, Elizabeth Schock, Joshua R. York, Austin P. Li, Ashlyn Y. Tu, Carole Labonne

Markey Cancer Center Faculty Publications

SoxB1 transcription factors (Sox2/3) are well known for their role in early neural fate specification in the embryo, but little is known about functional roles for SoxB1 factors in non-neural ectodermal cell types, such as the neural plate border (NPB). Using Xenopus laevis, we set out to determine whether SoxB1 transcription factors have a regulatory function in NPB formation. Here, we show that SoxB1 factors are necessary for NPB formation, and that prolonged SoxB1 factor activity blocks the transition from a NPB to a neural crest state. Using ChIP-seq, we demonstrate that Sox3 is enriched upstream of NPB genes in …


Response To Replication Stress And Maintenance Of Genome Stability By Wrn, The Werner Syndrome Protein, David K. Orren, Amrita Machwe Jul 2024

Response To Replication Stress And Maintenance Of Genome Stability By Wrn, The Werner Syndrome Protein, David K. Orren, Amrita Machwe

Markey Cancer Center Faculty Publications

Werner syndrome (WS) is an autosomal recessive disease caused by loss of function of WRN. WS is a segmental progeroid disease and shows early onset or increased frequency of many characteristics of normal aging. WRN possesses helicase, annealing, strand exchange, and exonuclease activities and acts on a variety of DNA substrates, even complex replication and re- combination intermediates. Here, we review the genetics, biochemistry, and probably physiological functions of the WRN protein. Although its precise role is unclear, evidence suggests WRN plays a role in pathways that respond to replication stress and maintain genome stability particularly in telomeric regions.


Decisions, Decisions: Dna Damage Induced Modification Of P53 And The Effect Of Modifications On P53 Differential Binding To The Dna, Savannah Gabrielle Keating Jul 2024

Decisions, Decisions: Dna Damage Induced Modification Of P53 And The Effect Of Modifications On P53 Differential Binding To The Dna, Savannah Gabrielle Keating

Theses and Dissertations

p53 is the most frequently mutated tumor suppressor protein in cancer. It is highly regulated, most often via post-translational modifications (PTMs). Different pathways and target genes are differentially activated by p53 and there is much left to understand how this occurs. The regulation of p53 at the post-translational level is incredibly important to its DNA damage response, and, therefore, it is understood that PTMs are often involved in the differential activation of pathways by p53. This project aimed to identify some of the types and locations of post-translational modifications on p53 in response to different modes of DNA damage with …


Exploring The Effects Of An Alfalfa Leaf-Derived Adsorbent On Microbial Community, Ileal Morphology, Barrier Function, And Immunity In Turkey Poults During Chronic Aflatoxin B1 Exposure, Maria De Jesus Nava-Ramirez, Jing Liu, Juan Omar Hernandez-Ramirez, Xochitl Hernandez-Velasco, Juan D. Latorre, Alma Vazquez-Duran, Guolong Zhang, Roberto Señas-Cuesta, Sergio Gomez-Rosales, Andressa Stein, Billy M. Hargis, Guillermo Tellez-Isaias, Abraham Mendez-Albores, Jesus A. Maguey-Gonzalez Jul 2024

Exploring The Effects Of An Alfalfa Leaf-Derived Adsorbent On Microbial Community, Ileal Morphology, Barrier Function, And Immunity In Turkey Poults During Chronic Aflatoxin B1 Exposure, Maria De Jesus Nava-Ramirez, Jing Liu, Juan Omar Hernandez-Ramirez, Xochitl Hernandez-Velasco, Juan D. Latorre, Alma Vazquez-Duran, Guolong Zhang, Roberto Señas-Cuesta, Sergio Gomez-Rosales, Andressa Stein, Billy M. Hargis, Guillermo Tellez-Isaias, Abraham Mendez-Albores, Jesus A. Maguey-Gonzalez

Poultry Science Faculty Publications and Presentations

This article follows-up on our recently published work, which evaluated the impact of the addition of an alfalfa leaf-derived adsorbent in the aflatoxin B1 (AFB1)-contaminated diet in regard to the production parameters, blood cell count, serum biochemistry, liver enzymes, and liver histology of turkey poults. This paper presents complementary results on microbial community, ileal morphology, barrier function, and immunity. For this purpose, 350 1-day-old female turkey poults were randomly distributed into five groups: (1) Control, AFB1-free diet; (2) AF, AFB1-contaminated diet at 250 ng/g; (3) alfalfa, AFB1-free diet + 0.5% ( …


Use Of Cobalt(Iii) And Copper(Ii) Complexes With Thiosemicarbazone Ligands And Berberine Chloride As Anti-Cancer Agents Against Triple Negative Breast Cancer, Duaa Rashad Alajroush Jul 2024

Use Of Cobalt(Iii) And Copper(Ii) Complexes With Thiosemicarbazone Ligands And Berberine Chloride As Anti-Cancer Agents Against Triple Negative Breast Cancer, Duaa Rashad Alajroush

Chemistry & Biochemistry Theses & Dissertations

It is a worrying fact that chemotherapeutic options for treating triple negative breast cancer are limited in nature, including the use of inorganic pharmaceuticals such as cisplatin and its analogues. It has been reported that cisplatin has undesirable side effects when used as a chemotherapeutic drug. As such, there is a need to use non-platinum-containing complexes as chemotherapeutic agents. Based on that issue, it has been reported by our research group and others that cobalt- and copper-containing complexes have shown great potential in anti-cancer properties when compared to cisplatin. In this research project, the cytotoxic effects of the following complexes: …