Biochemistry Commons^™

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 …

Development And Characterization Of Β-Cyclodextrin Inclusion Complexes With Enzalutamide For Easing Administration And Efficacy Of The Drug In Crpc, Meghana Kolli

Theses and Dissertations

Prostate cancer (PC) is prevalent among men in the US, often leading to castration-resistant prostate cancer (CRPC) with therapy. This is marked by androgen receptor (AR) overexpression, resistance, mutations, and splice variants. Enzalutamide (ENZ), a nonsteroidal antiandrogen, surpasses first-gen AR inhibitors like Bicalutamide. It's the go-to drug for CRPC. We explore ENZ for self-assembly complex formation, crucial for CRPC treatment. Using the solvent evaporation method, we developed β-cyclodextrin and ENZ self-assembly complexes (β-CD-ENZ). β-CD acts as both agent and solubilizer, FDA-approved and safe. Efficacy was tested on PC cell lines (C4-2B) and (22Rv1), including 3D cultures for cytotoxicity and a …

A Study Of The Effects Of An Amino Acid Residue On The Thermal Stability Of A Collagen Triple Helix In Varied Sequence Context, Ph, And Ionic Strength Of The Buffer, Zhenxun Xu

Theses and Dissertations

Collagen mimetic peptides are used broadly for collagen research and biomedical applications. Unlike the synthetic peptides obtained by solid phase chemical synthesis, recombinant peptides have more than 100 amino acid residues in length and are expressed in E. coli using designed genes. These longer peptides can offer improved, more native-like functions of native collagen for biomedical applications. One major challenge is the intrinsically low stability of native collagen, which has a melting temperature just above the physiological temperature of the organism. To understand how to enhance the thermostability of the peptides, I investigated the effects of amino acid sequences on …

Pipecolic Acid And Novel Insights Into Cerebral Malaria, Akua E. Mensah

Theses and Dissertations

Cerebral malaria (CM), a severe manifestation of Plasmodium infection, prompts our investigation into the nuanced role of pipecolic acid in its pathophysiology. To unravel the molecular intricacies, we conducted in vitro lysine labeling techniques of mice infected with P. berghei ANKA parasites, and human P. falciparum grown in vitro, aiming to discern the impact of Plasmodium on pipecolic acid production. Previous observations indicated an elevation in pipecolic acid levels correlating with neurological decline in children with CM. In our study, confirming elevated pipecolic acid presence in the plasma and brain tissues of CM patients and the animal model of CM, …

Genetics Of Lrg1 And Its Association With The Cardiometabolic Risk Traits In Mexican American Children And Adolescents, Aaron Rene Reyna

Theses and Dissertations

Leucine-rich alpha-2-glycoprotein 1 (LRG1) has become a major topic of research due to an increasing number of studies demonstrating its unique role in the pathogenesis of multiple human diseases including diabetes and cardiovascular disease. LRG1 has recently been identified as an adipokine, a signaling molecule secreted by adipose tissue. Furthermore, it has been correlated with intercellular signaling that promotes diet-induced hepatosteatosis and insulin resistance in mice. In this study, LRG1 serum concentrations were measured in a family-based cohort of 571 non-diabetic Mexican American children and adolescents aged 6-17 years old (mean age = 11.76 years and females = 48.2%) to …

Utilizing Nanodiamond For Antiretroviral Drug Delivery To Hiv Infected Microglial Cells, Ebenezer Owusu

Theses and Dissertations

Combination antiretroviral therapy (cART) is widely used to treat HIV infection, but it fails to eradicate viral reservoirs, such as microglia in the brain, leading to HIV-associated neurological disorders (HAND). Advances in nanomedicine have enabled the development of targeted drug delivery systems, and nanodiamonds (NDs) and fluorescent nanodiamonds (FNDs) have emerged as a potential solution due to their biocompatibility, non-toxic nature, and efficiency as drug carriers. Our study builds on previous findings that NDs can cross the blood-brain barrier (BBB), aiming to utilize NDs and FNDs for their added traceability. We propose a multifunctional nanodrug platform that leverages NDs and …

Effects Of Nitrogen Or Phosphorus Depletion On Lipid Production In Bracteacoccus Sp. And Tetrastrum Sp., Cassandra J. Po

Theses and Dissertations

As global energy demands have risen in the past decades, various species of microalgae have been chosen and used as sources of lipids for third-generation biofuel. I selected two species of green microalgae, Bracteacoccus sp. and Tetrastrum sp., from isolates from South Texas to determine their potential as sources of biofuel. For comparison, Chlamydomonas reinhardtii was used as a model organism. To evaluate lipid productivity under different nutrient regimens, the microalgae were grown in nutrient-replete growth media until the population had reached the end of the logarithmic phase (roughly 14 days), and then transferred into growth media depleted of nitrogen …

Role Of Interferon-Induced Protein With Tetratricopeptide Repeats 3 (Ifit3) In Hiv-1 Associated Neurodegenerative Disorder And Alzheimer’S Disease, Ranjit Kumar Das

Theses and Dissertations

The advent of cART has revolutionized the management of HIV-1 infection and saved the lives of millions of people worldwide. Yet, HAND continues to be clinically relevant with aging people with HIV-1 (PWH). The underlying mechanism of HAND remains poorly understood. In this regard. Signal transducer and activator of transcription 1(STAT1) and IFIT3 genes have been shown to induce neuroinflammation and neuronal cell death. However, the role of IFIT3 in HAND pathology has not been well established. Therefore, the present work investigated the significant role of IFIT3 gene in development of HAND. In the current study, …

Identification Of A Novel Target For Declustering Supernumerary Centrosomes In Triple Negative Breast Cancer, Priyanga J

Theses and Dissertations

Triple-negative breast cancer (TNBC) confers considerable interventional challenge owing to its massive heterogeneity, aggression and metastatic prowess. These facets are attributed to chromosomal instability (CIN), a feature consequent to TNBC cell’s ability to harbor more than two centrosomes (supernumerary centrosomes; SNCs).

In principle, if a normal cell possesses SNCs, uneven pull forces are generated consequent to multipolar spindle, which activates cellular surveillance. This ensures error-free mitosis by either repairing the error or, in an irreparable condition, driving cells to death. This averts the possibility of aneuploidy (fundamental to tumorigenesis).

Unfortunately, TNBC cells, despite harboring SNCs, have devised a survival strategy …

Illuminating Function And Enabling Inhibition At The Protein-Membrane Interface Of Glutathione Peroxidase 4., Courtney L. Labrecque

Theses and Dissertations

Membrane proteins act as gateways to cells and are responsible not only for signaling, lipid transport, and cellular homeostasis, but they are also integral in disease pathologies. One class of membrane proteins, peripheral membrane proteins (PMPs), reside in aqueous compartments of the cell until they are recruited to the membrane to perform their function. Glutathione peroxidase 4 (GPx4) is a PMP enzyme responsible for engaging the membrane and reducing lipid hydroperoxides, thereby preventing cellular death via ferroptosis. Due to its central function surrounding ferroptosis, GPx4 is an interesting drug target that has recently gained interest for inflammatory diseases as well …

Investigations Of A Nox2 Activator, P47phox, Px Domain Membrane Anchoring Interactions And Inhibition, Angela Develin

Theses and Dissertations

The regulation of cellular signaling across plasma membranes is a well-organized process through cross-talk of biomolecules such as proteins and membranes. Peripheral membrane proteins (PMPs) are a class of water soluble, membrane associated, proteins that play a critical role in transducing such signals. Due to the dynamic nature of their membrane interactions, relatively smooth surfaces, and general lack of deep ligand binding pockets, PMPs are commonly associated with an approximate 85% of the human proteome that is classified as ‘undruggable’ by current drug discovery methodologies. One such PMP, p47^phox, contains a PX domain which is essential in activation …

Mechanistic Analysis Of Four-Way Dna Junctions And Cytokine-Binding Aptamers For Therapeutic Interventions, Roaa S. Mahmoud

Theses and Dissertations

DNA is inherently dynamic and topologically diverse and can fold into many different structures. Besides the canonical Watson-Crick structure, other higher-order structures such as G-quadruplexes (G4), i-motifs (iM), and four-way DNA junctions are possible. Although these high-order DNA structures are known to form transiently, they are important due to the crucial roles they play in many cellular processes including DNA replication, recombination, and repair. Among these DNA structures, 4-way junctions (also known as Holliday junctions, HJ) which are formed during the repair of double-strand DNA breaks (DSBs) and interact with proteins have garnered significant attention due to their central role …

A Phytochemical Analysis Of Secondary Metabolites In Eupatorium Serotinum, Elise Snow

Theses and Dissertations

Phytochemistry, a subset of Natural Products Chemistry, studies chemically derived products from natural substances. Advances in this field have important applications in medicinal research due to the distinctive and unique properties of natural compounds. All metabolites are produced from the metabolic cycle, which is a pathway that provides energy for the organism. These metabolic compounds vary greatly and are classified based on their function within the organism. Primary metabolites are abundant and contribute to organism growth, development, and maintenance of energy. Secondary metabolites are found in lesser quantity and correlate to natural defense mechanisms. For example, salicylic acid is a …

Identification And Characterization Of Silk Gland Specific Ugt34 Gene In Helicoverpa Zea, Courtney Nicole Wynn

Theses and Dissertations

Uridine diphosphate glycosyltransferase (UGT) is a multigene family of enzymes responsible for catalyzing glycosylation of small hydrophobic molecules. Recently, a genomic analysis of the corn earworm (Helicoverpa zea) identified 45 different UGT genes. We discovered a UGT gene (UGT34) showing high levels of expression exclusively in the silk gland tissue. The expression levels of UGT34 were analyzed in different developmental stages and silk gland sub-segments, revealing that UGT34 is generally expressed at all larval instar stages and largely expressed in the middle and posterior subsegments of the silk glands. The soybean looper (Chrysodeixis includens), another noctuid …

Upland Cotton And Nematodes: An Analysis Of Historical Resistance, Upcoming Threats, And Co-Inoculation Effects, Amanda Gaudin

Theses and Dissertations

Upland cotton (Gossypium hirsutum ) is an important fiber crop grown throughout the southern United States. Plant-pathogenic nematodes are worm-like animals that feed on the roots of most agronomic crops, including cotton. The southern root-knot nematode (Meloidogyne incognita, RKN) and the reniform nematode (Rotylenchulus reniformis, RN) cause significant yield losses in cotton every year. Current sources of resistance are effective but limited, therefore historical screenings of cotton accessions were revisited in search for novel resistance sources. None were identified but many of the screened accessions possessed markers of known root-knot nematode and reniform nematode resistance. …

The Role Of Tc-Ptp-Mediated Suppression Of Autophagy During Skin Carcinogenesis, Obed Asare

Theses and Dissertations

Ultraviolet B (UVB) radiation can distort cellular homeostasis and predispose the skin to carcinogenesis. Amongst the deteriorating effects of the sun’s UVB radiation on cellular homeostasis is the formation of DNA photoproducts such as cyclobutene pyrimidine dimers. These photoproducts can cause significant changes in the structure and conformation of the DNA, inducing gene mutations which may accumulate to trigger the formation of skin cancer. Photoproducts are typically repaired by nucleotide excision repair. Notwithstanding, when the repair mechanism fails, apoptosis ensues to prevent the accumulation of mutations and to restore cellular homeostasis. We have identified T-cell protein tyrosine phosphatase (TC-PTP) as …

Artemisinin And Its Derivatives Reactions: Characterization Of The Reaction Products Using Lc/Tof Ms, Kogila Vijayan

Theses and Dissertations

Artemisinin (ART) is a sesquiterpene lactone and a popular malaria drug with potential anticancer properties. In this work, LC/TOF MS was used to investigate the reaction of ART with DNA bases and estradiol. ART-deoxyadenosine and ART-deoxycytidine interactions were studied in the presence of Fe (II) ions. ART-deoxyadenosine and ART-deoxycytidine reaction mixtures gave chromatographic signatures that remained unchanged at room temperature but grew after incubation at 37°C. The change in temperature from room temperature to 37°C was the main driver of adduct formation in these reactions. ART was found to react with Fe (II) ions as observed from several new chromatographic …

Physiological And Proteomic Analysis Of Soybean In Response To Drought And Heat Stress, Amandeep Kaur

Theses and Dissertations

Drought and temperature stress are the two most important factors limiting crop productivity. A physiological and proteomic analysis of soybean was performed to investigate the negative impact of these variables. The previous studies reported the beneficial effect of silicon under stress conditions. Silicon supplementation may promote plant growth under drought stress, although the mechanism to alleviate drought stress is uncertain. The proteomic analysis of chloroplast proteins was carried out to study the response of silicon supplementation under drought stress.

Similarly, temperature stress, mainly heat stress, has an adverse effect on soybean plants. The comparative analysis of two soybean cultivars, DS25-1 …

Preparation And Characterization Of Salvia Triloba Extract And Evaluation Of Its Cytotoxic Effect On Bone Cancer Cell Line, Basma Hossam Abdelmonem

Theses and Dissertations

Background: Osteosarcoma is a tumor of mesenchymal origin characterized by uncontrolled production of immature osteoid tissue. It is more common in children and adults over the age of 65. Many studies reported the cytotoxic effect of many plant extracts, including Salvia triloba, on different cancer cell lines when used alone or in combination with other chemotherapeutic agents.

Methods: In our study, the methanolic extract obtained from the air-dried leaves of Salvia triloba leaves from Palestine was screened for its total phenolic and flavonoid contents. The major components of phenolics and flavonoids were detected using LC-QToF-MS technique. The two phenolics …

Dna Damage Response Activates The Electron Transport Chain And Oxidative Metabolism By Two Parallel Mechanisms, Shreya Nagar

Theses and Dissertations

The DNA damage response (DDR) is an evolutionarily conserved process essential for cell survival. Major part of DDR is coordinated by DNA damage checkpoint (DDC). In addition to DDC, eukaryotic cells also have DNA replication checkpoint (DRC) that is distinct from the DDC and specifically signals slowly progressing or arrested replication forks. DDR involves stalling or arrest of the cell cycle, initiation of DNA repair, and altered regulation of transcription, translation, and the ubiquitin-proteasome system. DDR also triggers transcription shut-off of histone genes. One of the key outcomes of DDC/DRC activation is the increased synthesis of the deoxyribonucleoside triphosphates (dNTPs), …

Treponema Denticola Synthesizes C-Di-Amp And Encodes The Cdaa-Type Diadenylate Cyclase Cdaa, Claire R. O'Brien

Theses and Dissertations

Periodontitis is a form of oral disease characterized by dysbiosis of the oral microbiome, leading to inflammation, bone resorption, and in severe cases, entire tooth loss, affecting 42% of adults in the US. One of the bacteria most associated with periodontal disease progression is Treponema denticola (Td), an oral spirochete which inhabits the mouth in small quantities during health but which can dominate the biofilms that form during periodontal disease. The ability of Td to survive in a disease environment and contribute to the progression of disease requires the use of robust signaling networks. Analysis of Td cultures …

Dynamics Of Redox-Driven Molecular Processes In Local And Systemic Plant Immunity, Philip Berg

Theses and Dissertations

The work here presents two main parts. In the first part, chapters 1 – 3 focus on dynamical systems modeling in plant immunity, whereas chapters 4 – 6 describe contributions to computational modeling and analysis of proteomics and genomics data. Chapter 1 investigates dynamical and biochemical patterns of reversibly oxidized cysteines (RevOxCys) during effector-triggered immunity (ETI) in Arabidopsis, examines the regulatory patterns associated with Arabidopsis thimet oligopeptidase 1 and 2’s (TOP1 and TOP2), roles in the RevOxCys events during ETI, and analyzes the redox phenotype of the top1top2 mutant. The second chapter investigates the peptidome dynamics during ETI …

Molecular Basis Of Viroid Rna-Templated Transcription, Shachinthaka D. Dissanayaka Mudiyanselage

Theses and Dissertations

Transcription is a fundamental process catalyzed by DNA-dependent RNA polymerases (DdRPs). Interestingly, some DdRPs can use both DNA and RNA as templates for transcription. This RNA-dependent RNA polymerase (RdRP) activity of DdRPs is used by RNA-based pathogens such as viroids and hepatitis delta virus for replication. In addition, RdRP activity of DdRPs widely occurs in various organisms to regulate gene transcription. Despite the importance of this intrinsic RdRP activity of DdRPs, associated factors and mechanisms are in their infancy stage. We employed potato spindle tuber viroid (PSTVd) as a model to study RNA-templated transcription. Here, we present evidence showing that …

Classification Models For 2,4-D Formulations In Damaged Enlist Crops Through The Application Of Ftir Spectroscopy And Machine Learning Algorithms, Benjamin Blackburn

Theses and Dissertations

With new 2,4-Dichlorophenoxyacetic acid (2,4-D) tolerant crops, increases in off-target movement events are expected. New formulations may mitigate these events, but standard lab techniques are ineffective in identifying these 2,4-D formulations. Using Fourier-transform infrared spectroscopy and machine learning algorithms, research was conducted to classify 2,4-D formulations in treated herbicide-tolerant soybeans and cotton and observe the influence of leaf treatment status and collection timing on classification accuracy. Pooled Classification models using k-nearest neighbor classified 2,4-D formulations with over 65% accuracy in cotton and soybean. Tissue collected 14 DAT and 21 DAT for cotton and soybean respectively produced higher accuracies than the …

Water-Soluble Porphyrin Complexes For The Biological Inactivation Of Fentanyl, Anneli Nina

Theses and Dissertations

This work aimed to investigate the degradation of fentanyl in aqueous solutions using unsupported water-soluble cobalt(III) porphyrins (55 and 56), AuNP supported water-soluble cobalt(III) porphyrins (67 and 68), and liposome supported water-soluble cobalt(III) porphyrins (69 and 70). Complexes 55, 56, 68, and 69 have been shown to remove fentanyl from aqueous solutions at 37 ºC. The degradation of fentanyl, and the identification of breakdown products were analyzed with the use of time-of-flight mass spectrometry (TOFMS). Complex 55 has been shown to completely degrade fentanyl at 37 ºC in as little as two hours with a 400 mol% catalyst loading. Complex …

Studies On The Impact Of An Insect Growth Regulator And Host Plant On Reproductive Physiology Of Lygus Lineolaris, James Houston Chance Anderson

Theses and Dissertations

The tarnished plant bug, Lygus lineolaris, is an economically important polyphagous pest with a broad host range. With occurrence of insecticide resistance, strategies to limit its ability to reproduce, which would curb population growth, are becoming increasingly more valuable. Strategies toward this goal include the application of insect growth regulators (IGRs) and utilization of resistant cotton lines. This thesis summarizes experiments that elucidate the physiological underpinnings of the mode of action of novaluron, an IGR, and a cotton chromosome substitution (CS) line on the reproductive physiology of L. lineolaris. Investigations reported herein indicate that novaluron inhibits oviposition by …

Novel Strategies In Near Infrared Spectroscopy (Nirs) And Multivariate Analysis (Mva) For Detecting And Profiling Pathogens And Diseases Of Agricultural Importance., Johjan Mariana Santos Rivera

Theses and Dissertations

The time required for the identification of pathogens is an important determinant of infection-related mortality rates and disease spread for species of relevance in agriculture. Conventional identification methods require a processing time of at least one to twenty days. Therefore, inaccurate empirical treatments are often provided while awaiting further identification, such that most cases progress with further aggravation of symptoms, contamination of other animals or plants, generating economic loss from decreased yield, and increased mitigation costs. Thus, there is a need for innovative, non-destructive, and rapid analytical techniques that provide reagent-free, portable, reliable, and holistic approaches to detect diseases in …

Optimized Selenium Status, Gut Microbiota, And Type 2 Diabetes, Ying-Chen Huang

Theses and Dissertations

We have previously demonstrated that long-term dietary Se deficiency in old Terc^-/- mice with humanized telomeres induces type-2 diabetes and exacerbates age-dependent increases in the abundance of A. muciniphila and Lachnospiraceae, which are related to obesity and metabolic syndromes. The objectives of this dissertation are: 1) to determine the minimum intake of Se required for type 2 diabetes prevention in middle-aged mice; 2) to evaluate the efficacy of A. muciniphila and R. torques (a Lachnospiraceae family member) to intervene dietary Se deficiency-induced type 2 diabetes and the underlying mechanisms; 3) to assess sex differences in the responses to …

Eukaryotic Initiation Factor 4e (Eif4e) In Complex With Eif4e Binding Protein 1 (4e-Bp1) Binds With Higher Affinity To M7gpppn Cap Of A Subset Of Human Mrnas, Izza F. Nawaz

Theses and Dissertations

Fluorescence anisotropy binding assays were used to analyze the binding of eIF4E in complex with 4E-BP1 onto the 5’ m7G cap of a subset of mRNA that are known to carry cap-independent translation. These studies suggest that 4E-BP1 increases eIF4E binding affinity to 5’cap of both FGF-9 and HIF-1𝝰.

Identification Of Novel Phosphorylation Sites In Sars-Cov-2 Nucleocapsid Protein, Josie Daldegan Rezende

Theses and Dissertations

COVID-19, the 2019 disease outbreak, continues to cause severe mortality worldwide. Fast and reliable tests that identify the SARS-CoV-2 virus, which is responsible for causing the COVID-19 disease, are crucial for controlling the spread of the virus. Antigen tests are ideal for the rapid diagnosis of COVID-19. Current antigen tests for COVID-19 detect the SARS-CoV-2 nucleocapsid (N) protein. The nucleocapsid is the most abundant protein produced by the virus upon infection, which makes it a superior target for detection by an antigen test. Nucleocapsid proteins from several coronaviruses, including SARS, have previously been shown to be modified by posttranslational modification …