Biochemistry, Biophysics, and Structural Biology Commons^™

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, …

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 …

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 …

Role Of Grb2 Intracellular Localization In Progesterone Receptor Positive Breast Cancer, Nattamolphan Wittayavimol

Chulalongkorn University Theses and Dissertations (Chula ETD)

Progesterone receptor (PR) extranuclear signaling mediates mainly through PR polyproline domain (PPD) interaction with SH3 domain of cytoplasmic signaling molecules. PR-PPD interfered with Grb2-SOS binding through SH3 interaction resulting in decreased cell proliferation and correlates with a good prognosis in PR positive breast cancer. Grb2 is a key adaptor molecule and expressed in both nucleus and cytoplasm. We hypothesized that change in Grb2 localization alters PR transcription resulting in better clinical outcomes in PR positive breast cancer. BT-474 breast cancer cells expressing inducible Grb2-SV402x (nuclear Grb2, nuGrb2) or Grb2-MYR (membrane Grb2, memGrb2) were constructed. MemGrb2-BT-474 showed higher levels of PR …

Roles Of Progesterone Signaling On Dna Repair And Cell Survival In Ovarian Cancer Cells, Pattarasiri Rangsrikitphoti

Chulalongkorn University Theses and Dissertations (Chula ETD)

Every year over 300,000 women worldwide are diagnosed with ovarian cancer and half of these patients die from this disease. The symptoms of ovarian cancer are very general and often confused with other common female diseases making ovarian cancer a challenging disease to diagnose and treat. Platinum-based chemotherapy, including cisplatin, stands as the first-line treatment for ovarian cancer. However, chemotherapy resistance remains a continuing problem, contributing to a high mortality rate. Progesterone receptor (PR) signaling has been implicated in various aspects of ovarian cancer biology. Clinical studies show a positive correlation between PR expression, improved patient survival and cisplatin response, …

Cisplatin - Loaded Calcium Citrate Nanoparticlesfor Inhibition Of Lung Cancer Cell Growthand Quantum Mechanical Study Of Cisplatin And Citrate, Lipika Oopkaew

Chulalongkorn University Theses and Dissertations (Chula ETD)

The International Organization for Research on Cancer (International Agency for Research on Cancer (IARC) issued a statement saying lung cancer is a cancer with high incidence rates of new cases and deaths. Although there are current therapeutic approaches such as surgery, radiation therapy, and chemotherapy. However, these treatments exhibit ineffectiveness; the main limitation is severe side effects to normal cells or non-target organs. To address this challenge, the development of targeted therapy by nanoparticle-based drug delivery system is applied to increase drug stability and control the specificity to cancer cells with target-specific proteins that play an important role in intracellular …

Protein Extraction And Purification By Differential Solubilization, Barry J. Ryan, Gemma K. Kinsella, Gary T. Henehan

Books/Book Chapters/ Proceedings

The preparation of purified soluble proteins for biochemical studies is essential and the solubility of a protein of interest in various media is central to this process. Selectively altering the solubility of a protein is a rapid and economical step in protein purification and is based on exploiting the inherent physicochemical properties of a polypeptide. Precipitation of proteins, released from cells upon lysis, is often used to concentrate a protein of interest before further purification steps (e.g., ion exchange chromatography, size exclusion chromatography etc).

Recombinant proteins may be expressed in host cells as insoluble inclusion bodies due to various influences …

Apobec3 Regulation By Thyroid Hormone, Michelle Santiago

All Graduate Theses, Dissertations, and Other Capstone Projects

Thyroid hormone (TH) is crucial for many biological processes, including the development of the auditory system. Appropriate thyroid hormone signaling is important for the development of the cochlea, leading to the successful onset of hearing. More specifically, TH influences the timing of remodeling of the greater epithelial ridge (GER), a transient cochlear structure that secretes proteins that contribute to the formation of the tectorial membrane. Developmental hypothyroidism results in delayed GER regression, whereas excess TH results in premature remodeling. Both conditions result in deafness. However, it is unknown how TH mediates GER remodeling. Expression profiling identified APOBEC3 (A3) as a …

The Molecular Mechanisms Of Ifn-Γ Promoted Necroptosis In Macrophages, Meghan R. Vogt

Biotechnology Theses

Necroptosis, a form of programmed lytic cell death, has emerged as a driving factor in the pathogenesis of acute lung injury. One specific inflammatory mediator that is of interest is interferon-γ (IFN-γ). Our laboratory has reported that IFN-γ is the most potent enhancer of necroptosis in primary lung epithelial cells and macrophages by upregulating MLKL expression. How IFN-γ enhances necroptosis and MLKL upregulation is currently unknown. In this research, we utilized multiple approaches to study the potential molecular mechanisms of IFN-γ promoted necroptosis in macrophages. We found that MLKL and ZBP1 are significantly upregulated by IFN-γ through an unknown pathway …

Investigating The Relationship Between Metabolic Reprogramming And Peripheral Cd4+ T-Cell Inflammation In Human Type 2 Diabetes Pathogenesis, Gabriella Kalantar

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Chronic, low-grade systemic inflammation rises in obesity and promotes type 2 diabetes (T2D). Circulating immune cells are key indicators of obesity and T2D pathogenesis. T cells outnumber monocytes, in blood, suggesting that T cells might fuel peripheral inflammation in obesity/T2D. Our lab’s work supports this idea by identification of a Th17 cytokine profile in T2D from T-cell stimulated peripheral blood mononuclear cells. Work described herein further supported this work by demonstrating that T cells dominate peripheral inflammation over monocytes across the spectrum of obesity and glycemic control. Our lab has also recently shown that inflammation changes during prediabetes (preT2D), identified …

Developing A Biocatalytic Toolbox To Aid In Understanding Nucleoside Antibiotics, Jasmine Brianna Woods

Theses and Dissertations--Pharmacy

Antibiotic resistance happens when bacteria develop the ability to survive medications that normally terminate them. Instead, these super germs are able to survive in the body and produce a community of antibiotic resistance germs which can cause human fatalities. It is important to discover and develop new compounds and molecules that will improve this clinical obstacle. This research focused on analyzing the biosynthesis that incorporates distinctive chemical characteristic of various nucleoside antibiotics, ß-hydroxy amino acids and α-methyl-amino acids. ß-hydroxy amino acids and α-methyl-amino acids are considered an important class of industrially useful compounds, particularly for pharmaceutical development, and are found …

Impact Of Sample Conditions On Dna Phosphodiester Backbone Bi/Bii Conformational Equilibrium Dynamics, Autumn C. Pilarski

Graduate Theses/Dissertations

DNA damage, such as single base lesions and mismatches, is highly prevalent within cells. If these DNA damage events are not repaired, they could lead to mutations and thus disease and cancer. Intricate repair mechanisms are in place to fix these damage events, one such being Base Excision Repair (BER) and associated enzyme: Thymine DNA Glycosylase (TDG). The first step of this repair process, recognition of the lesion by TDG, is not well understood. The following thesis presents results to better understand the fundamental biophysical question of how a DNA lesion within a mismatch context is recognized in a million …

Investigating Mirna Regulation Of The Human Apobec3 Enzymes, William Dietrich

All Graduate Theses, Dissertations, and Other Capstone Projects

The human apolipoprotein B mRNA editing enzyme catalytic polypeptide 3 (APOBEC3, A3) are a family of proteins consisting of seven enzymes, A3A, B, C, D, F, G and H, which function as cytosine deaminases. The enzymes’ purpose in the cell is to mutate viral DNA during infection hindering or stopping replication of viruses such as human papillomavirus, herpes simplex virus, and HIV-1. Several of the A3 enzymes have also been implicated in contributing to cancers such as head and neck and breast cancers by mutating cellular genomic DNA, making the ability to control A3 expression an attractive target for cancer …

Novel Amino Acids Dictate Differences In Sivmac239 And Hiv-2 Rod9 Vpx Cellular Localization, Hunter D. Mayhew

All Graduate Theses, Dissertations, and Other Capstone Projects

Vpx is a protein encoded by Human Immunodeficiency Virus Type 2 (HIV-2) and specific Simian Immunodeficiency Viruses (SIVs) that is essential for successful infection of non-dividing myeloid cells. Vpx facilitates viral replication by trafficking the viral genome into the nucleus of infected cells and targeting the primarily nuclear innate immune protein SAMHD1 for proteasomal degradation. Considering that these activities occur at the nucleus, we hypothesized that Vpx nuclear localization would be tightly correlated with these functions. To assess this, site directed mutagenesis in combination with confocal microscopy or Western Blotting analyses were utilized to evaluate the determinants of nuclear accumulation …

Investigation Of Mechanical Regulation On Stat3 Activity And Mmp Production, Jaxson R. Libby

Honors Theses and Capstones

Transcription factor, STAT3, is inappropriately expressed in cancer cells, and has contrasting activation in 2D versus 3D microenvironments. 2D plates are often used for drug screening and do not always recapitulate in vivo responses. To combat inaccurate 2D drug studies, a 3D hydrogel was created to support the growth of cancer cells into a tumor-like environment. The hydrogel consists of a biocompatible dextran homopolysaccharide, cell adhesion RGD sequences, and crosslinker MMP labile peptides. A pH dependent reaction couples the RGD sequences to dextran then the polymers are crosslinked into a gel. Crosslinking is accomplished using terminal cysteine peptide sequences, allowing …

Molecular Mechanisms Of Wild-Type And Mutant Prion Formation, Daniel J. Walsh

Dartmouth College Ph.D Dissertations

Prion diseases are a class of infectious neurodegenerative disorders which affect humans and many other mammalian species. The causative agent is a unique pathogen known as a prion or PrPSc, a misfolded form of a host-encoded glycoprotein which replicates by templated conformational change. Distinct strains of prions with unique phenotypic and pathologic presentations appear to be encoded by subtle conformational changes within the misfolded protein. While the general manner of prion transmission is known, our detailed understanding of these mechanisms remains incomplete, limiting efforts for the discovery or design of therapeutic treatments for these fatal diseases. In vitro synthesis of …

Interactomics And Targeted Protein Degradation For Kinase Substrate Discovery, Juan C. Mercado Del Valle

Dartmouth College Ph.D Dissertations

Reversible phosphorylation is one of the most important post translational modifications that has allowed us as a species to quickly adapt to changing molecular environments due to external stimulation. This process is only capable through the activity of kinases to carry out the targeting of specific substrates defined by their recognition motif allowing for selective phosphorylation and activation and inactivation of distinct pathways as well as other changes that permit cell survival. By being so important for the maintenance of the cells disruption often leads to worsening of the cells, leading to various diseases like cancer, immunological and neurodegenerative disorders. …

Specialized Metabolism In Retina, Retinal Pigmented Epithelium, And Testis, Siyan Zhu

Graduate Theses, Dissertations, and Problem Reports (ETD)

The retina and its neighboring retinal pigmented epithelium (RPE) are high energy-demanding and metabolically active tissues with specialized and complementary metabolism. They are metabolically interdependent and impact each other’s viability. Interestingly, many of the metabolic features in the retina and RPE are shared with the testis. For example, testis is also energy costly due to continuous sperm differentiation and it has similar metabolic inter-dependence between different testis cells. Both the retina and testis are vulnerable to mitochondrial metabolic impairments.

We conducted three research projects to understand 1) the nutrient utilization and communication in retina and RPE; 2) The profiling of …

Multilevel Computational Investigation Into The Catalytic Mechanisms Of Matrix Metalloproteinase-1 And Fat Mass And Obesity-Associated Enzyme, Ann Varghese

Dissertations, Master's Theses and Master's Reports

Enzymes are biological macromolecules, typically proteins, that efficiently accelerate the rate of chemical reactions. Their remarkable catalytic power plays a vital role in essential processes across all kingdoms of life. Nowadays, computational chemistry methods provide valuable insights into enzymatic functions aiding our understanding of biological processes and providing advancements in fields such as biomedical sciences, biomimetic catalysis, drug design and biotechnology. This dissertation employs multilevel computational chemistry methods to investigate the structure-function relationships and the catalytic mechanisms of two metalloenzymes -Zn(II)-dependent matrix metalloproteinase-1 (MMP-1) and non-heme Fe(II)/2-oxoglutarate (2OG) dependent fat-mass and obesity-associated (FTO) enzyme. Chapter 2 explores the role of …

Multiscale Molecular Modeling Studies Of The Dynamics And Catalytic Mechanisms Of Iron(Ii)- And Zinc(Ii)-Dependent Metalloenzymes, Sodiq O. Waheed

Dissertations, Master's Theses and Master's Reports

Enzymes are biological systems that aid in specific biochemical reactions. They lower the reaction barrier, thus speeding up the reaction rate. A detailed knowledge of enzymes will not be achievable without computational modeling as it offers insight into atomistic details and catalytic species, which are crucial to designing enzyme-specific inhibitors and impossible to gain experimentally. This dissertation employs advanced multiscale computational approaches to study the dynamics and reaction mechanisms of non-heme Fe(II) and 2-oxoglutarate (2OG) dependent oxygenases, including AlkB, AlkBH2, TET2, and KDM4E, involved in DNA and histone demethylation. It also focuses on Zn(II) dependent matrix metalloproteinase-1 (MMP-1), which helps …