Biochemistry Commons^™

Improvement Of Single-Crystal Structures Of Very Heavy Element Compounds By Refining Anomalous Dispersion Parameters, Florian Meurer, Gregory Morrison, Birgit Hischa, Hans Conrad Zur Loye, Christoph Hennig, Michael Bodensteiner

Faculty Publications

Refining the anomalous dispersion parameters of the four uranium compounds NaUF5, NaU2F9, Cs2(UO2)TiO4, and Cs2(UO2)Ti2O6 gave insights into the crystallographic model improvement of very heavy atoms. We found that the values for the dispersive and absorptive parts, f′ and f″, closely followed the X-ray absorption spectra on their L3, L2, and L1 edges. The obtained values are sensitive to the chemical environment at each crystallographically independent position. An incorrect treatment of the anomalous dispersion correction can lead to a wrong crystallographic model. The above-mentioned, already published structures were improved by this process. General guidelines were given for the crystal structure …

Unraveling The Role Of Hid-1: Insights Into Sgii Regulation, Breanna L. Sellers

Electronic Theses and Dissertations

The regulated secretory pathway is important for the secretion of hormones and neuropeptides from large dense core vesicles (LDCVs). Dysregulation of the biogenesis of LDCVs can result in metabolic and neurological diseases. Recent studies have suggested that the peripheral membrane protein HID-1 plays a role in the sorting and storage of granins which contribute to LDCV biogenesis. To further understand how HID-1 influences the regulation of granins, we investigated potential HID-1 interactors. We determined that while HID-1 is likely functioning in the same pathway as USP25, a deubiquitinating enzyme (DUB), the cause of reduced cellular SgII levels is likely not …

Sequence Specificity Of Non-Structural Protein 15 From Sars-Cov-2, John Vincent Mcguire

Electronic Theses and Dissertations

The SARS-CoV-2 virus was recently able to cause a global pandemic, largely due to the asymptomatic period that occurs during initial infection. During this period, patients are infectious but do not exhibit symptoms, resulting in the unintentional spread of the virus. This occurs because the virus effectively avoids detection by the immune system during the early stages of infection, and as symptoms are the result of immune system activation, they never manifest. Non-structural Protein 15 (Nsp15) is one of the tools the virus uses to remain undetected, via its degradation of Pathogen-Associated Molecular Patterns (PAMPs) that would otherwise be recognized …

Molecular Docking, Pharmacological Profiling, And Molecular Dynamics Simulation Of Potential Antihyperuricemic Agent From Secondary Metabolites Of Dillenia Philippinensis Rolfe (Dilleniaceae), Louie Rince C. Suyo, John P. Paulin, Nicole Clarence Louise L. Gapaz, Markus Brent S. Arevalo, Vince Tyrell P. Yongco, Librado A. Santiago

Karbala International Journal of Modern Science

Crystal accumulation in the joints due to increased serum uric acid (sUA) may lead to an inflammatory condition called gout. Increased sUA is caused by the excessive reabsorption of the urate anion transporter-1 (URAT-1). Therefore, URAT-1 inhibition will promote uric acid excretion and reduce the risk of having gout. Dillenia philippinensis Rolfe, often known as katmon, is an endemic plant in the Philippines with bioactive compounds associated with several therapeutic benefits. The present study represents the first scientific inquiry into the antihyperuricemic potential of compounds isolated from D. philippinensis. This study aimed to assess the interaction of URAT-1 with …

Structural Basis For Substrate Binding And Selection By Human Mitochondrial Rna Polymerase, Karl Herbine, Ashok Nayak, Dmitry Temiakov

Department of Biochemistry and Molecular Biology Faculty Papers

The mechanism by which RNAP selects cognate substrates and discriminates between deoxy and ribonucleotides is of fundamental importance to the fidelity of transcription. Here, we present cryo-EM structures of human mitochondrial transcription elongation complexes that reveal substrate ATP bound in Entry and Insertion Sites. In the Entry Site, the substrate binds along the O helix of the fingers domain of mtRNAP but does not interact with the templating DNA base. Interactions between RNAP and the triphosphate moiety of the NTP in the Entry Site ensure discrimination against nucleosides and their diphosphate and monophosphate derivatives but not against non-cognate rNTPs and …

Informatics-Based Discovery Of New Natural Products, Their Biosynthesis, And Their Biological Roles, Ethan Older

Theses and Dissertations

In this work, genome mining and biosynthetic knowledge are applied for the discovery of new natural products, their biosynthetic pathways, and their promising biological activities and roles through the development of two unique new informatics-based approaches.

In chapter one, an overview of microbial natural product biological functions and biosynthesis is provided. The use of bioinformatics leveraging microbial natural product biosynthetic knowledge is also introduced. This chapter highlights the importance and need for developing innovative approaches to accessing microbial natural products, a vastly untapped source of new molecules with promising biological activities.

In chapter two, a correlational network linking the gene-encoded …

Investigating The Oncogenic Role Of Nkx3.1 In Prostate Cancer, Audris Budreika

Master's Theses

Prostate cancer is a unique disease in that it is fueled by androgen receptor (AR) signaling. In the clinic, AR signaling is disrupted by removing androgens via chemical castration and employing AR-antagonists such as enzalutamide. Unfortunately, these therapies are short-lived, resistance sets in, and tumors evolve to a form of the disease called castration-resistant prostate cancer (CRPC). At this stage, therapeutic options are virtually exhausted and palliative care is pursued. There is a growing need to characterize other molecular players that cooperate with AR or play a unique role in CRPC on their own. One such potential candidate is the …

Quantification Of Immunometabolite Derived Protein Modifications During Mitochondrial Metabolic Stress, Justin Hunter Cox

Theses and Dissertations

The immunometabolite itaconate accumulates during lipopolysaccharide (LPS) stimulation of macrophages and microglia. Itaconate non-enzymatically reacts with cysteine residues to generate 2,3-dicarboxypropylcysteine (2,3-DCP), referred to as protein dicarboxypropylation. The tricarboxylic acid (TCA) cycle metabolite fumarate non-enzymatically reacts with the amino acid cysteine to form S-(2-succino)-cysteine (2SC), resulting in irreversible protein succination. Since fumarate and itaconate levels dynamically change in activated immune cells, the levels of both 2SC and 2,3-DCP reflect the abundance of these metabolites and their capacity to modify protein structure and function. I generated esters of 2SC and 2,3-DCP from protein hydrolysates and used stable isotope dilution liquid chromatography-tandem …

Design Of An Artificial Transcription Factor For Inducing Potent Interferon-Γ Signals, Ashley King

Theses and Dissertations

Cytokines are small immune signaling proteins responsible for cellular communication and their levels are tightly regulated throughout immune recognition and defense. Interferon gamma is a key cytokine responsible for upregulation of antigen presentation and supports the differentiation of pro-inflammatory effector cells. Due to its role in regulation, excess interferon gamma is cleared from the body limiting the success of interferon gamma immunotherapies. This study reports the design and validation of an artificial transcription factor (ATF) that induces endogenous interferon gamma expression. The transcription factor contains zinc finger proteins to recognize the interferon gamma gene and an activation domain to promote …

Characterizing The Role Of The Escherchia Coli Monothiol Glutaredoxin, Grxd, As An Iron-Sulfur Cluster Carrier Protein, Claire Elizabeth Fisher

Theses and Dissertations

Iron-sulfur (Fe-S) clusters are important cofactors with a primary role of electron transport that are required by proteins involved in wide range of biological pathways such as respiration, photosynthesis, and DNA repair. In Escherichia coli (E. coli), the assembly and transfer of these clusters to their target apo-protein is a highly coordinated process encoded by the multiprotein systems iscRSUAhscBAfdx and sufABCDSE operons. These clusters are assembled on a scaffold protein, where they are then transferred to a carrier protein that will deliver the cluster to the target apo-protein. The Isc and Suf systems contain their own carrier proteins IscA …

Macromolecular Crowding Effects On Enzymes That Display Non-Hyperbolic Kinetics, Kelsey A. Aldrich

Electronic Theses and Dissertations

Macromolecules occupy up to 30% of a cell's volume, yet the in vitro study of biological processes is almost exclusively performed in dilute solutions that fail to approximate the crowded interior of a cell. A growing body of literature has identified that macromolecular crowding has significant effects on a number of biochemical processes, including enzymatic activity. However, changes in kinetic parameters with increased macromolecule concentrations have only been determined for enzymes that follow hyperbolic Michaelis-Menten kinetics, despite the fact that over 25% of enzymes deviate from this model. Here, we perform the first characterization of macromolecular crowding effects on …

Role Of Pycr2 In Colorectal Cancer, Raju Lama Tamang

Theses & Dissertations

Despite significant progress in clinical management, colorectal cancer (CRC) remains the 3rd most common cause of cancer-related deaths. A positive association of PYCR2 (Pyrroline-5-carboxylate reductase-2), a terminal enzyme of proline metabolism, with CRC aggressiveness was recently reported including by us. However, how PYCR2 promotes colon carcinogenesis remains ill understood. In our studies, comprehensive in-silico and biochemical evaluations were performed along with genetic manipulations and in-vivo tumor growth assays to gain mechanistic understanding. Results showed that PYCR2 expression was significantly upregulated in CRC and associated with poor patient survival specifically among PYCR isoforms (PYCR-1, -2 and -3). Genetic inhibition of PYCR2 …

Determining If Cx45 Acts As An Arrythmogenic Substrate In The Diseased Myocardium, Stephen R. Sobota

Theses & Dissertations

Proper contraction of the heart relies on gap junction channels (GJCs) composed of Cx40 and Cx43 in the atrial and ventricular tissues which mediate electrical conductance in the working myocardium. Also expressed is Cx45, which is limited to the pacemaker system. Studies in diseased human hypertrophic cardiac tissue have shown expression of Cx45 and decrease of Cx43 in the myocardium. Cx43 and Cx45 in vitro form heterometric GJCs, where the channel characteristics (metabolite transfer, electrical conductance, etc.) resemble those of Cx45. There is little-to-no data showing whether GJCs composed of Cx43 and Cx45 in cardiac hypertrophy result in altered conductance. …

Stem-Loop And Circle-Loop Tads Generated By Directional Pairing Of Boundary Elements Have Distinct Physical And Regulatory Properties, Wenfan Ke, Miki Fujioka, Paul Schedl, James Jaynes

Department of Biochemistry and Molecular Biology Faculty Papers

The chromosomes in multicellular eukaryotes are organized into a series of topologically independent loops called TADs. In flies, TADs are formed by physical interactions between neighboring boundaries. Fly boundaries exhibit distinct partner preferences, and pairing interactions between boundaries are typically orientation-dependent. Pairing can be head-to-tail or head-to-head. The former generates a stem-loop TAD, while the latter gives a circle-loop TAD. The TAD that encompasses the Drosophila even skipped (eve) gene is formed by the head-to-tail pairing of the nhomie and homie boundaries. To explore the relationship between loop topology and the physical and regulatory landscape, we flanked the nhomie boundary …

Assessment Of Tripeptides Self-Assembly & Er Stress On Cell Viability And Exosome Secretion In Mda-Mb231, Azmat Parveen

Theses and Dissertations

This study delves into the effects of tripeptides KYpF and WYpK(NBD) on MDA-MB-231 cells, uncovering KYpF's ability to reduce cell proliferation and exosome secretion in peptide treated cells. Conversely, WYpK(NBD) demonstrated significant toxicity at 10 μM. These insights pave the way for optimizing peptide-based cellular treatments for exosome secretion purposes.

G12/13 Signaling In Asthma, Elizabeth L. Mcduffie, Reynold A Panettieri, Charles P. Scott

Department of Biochemistry and Molecular Biology Faculty Papers

Shortening of airway smooth muscle and bronchoconstriction are pathognomonic for asthma. Airway shortening occurs through calcium-dependent activation of myosin light chain kinase, and RhoA-dependent calcium sensitization, which inhibits myosin light chain phosphatase. The mechanism through which pro-contractile stimuli activate calcium sensitization is poorly understood. Our review of the literature suggests that pro-contractile G protein coupled receptors likely signal through G12/13 to activate RhoA and mediate calcium sensitization. This hypothesis is consistent with the effects of pro-contractile agonists on RhoA and Rho kinase activation, actin polymerization and myosin light chain phosphorylation. Recognizing the likely role of G12/13 signaling in the pathophysiology …

Detection Of Cryptosporidium Spp. In Surface Water And Tissues Of Bivalves In Waterways Of Coney Island, New York (Usa), Manasvi Patel

Biochemistry and Molecular Biology

Combined sewer overflows (CSOs) are major sources of pollutants such as microbial pathogens, total suspended solids (TSS), oxygen depleting substances, toxicants, and nutrients. Untreated wastewater contains parasites like Giardia, Cryptosporidium and Entamoeba which impact human health. Cryptosporidium is the leading cause of diarrheal diseases which spreads through contaminated water supplies. Our research on Coney Island in Brooklyn investigated the amount of Cryptosporidium oocysts found in the water and bivalves/shellfish tissue and to supports a parallel study examining both people's use of waterways around Coney Island (for religious ceremonies, fishing, foraging, swimming, etc.) and their perceptions of how polluted the …

Structure-Function Relationships In Neurodegenerative And Infectious Diseases: Biophysical Characterization Of Rna Secondary Structures By Computational Techniques, Kendy Guarinoni

Electronic Theses and Dissertations

The research described in this dissertation focuses on the investigation of the structure and dynamics of regions of RNA implicated in two diseases: COVID-19 and amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD). Both studies sought to create experimentally corroborated models that were used to characterize the structure and dynamics of the C9orf72 repeat expansion and the s2m region in coronaviruses, respectively and provided the foundation for future work. In our work involving the s2m region of SARS-CoV-2, the virus responsible for COVID-19, we determined that the homology modeling approach commonly used to derive atomistic structures when no coordinates are available yields a …

Elucidating The Roles Of Septin Proteins In Thermotolerance And Cell Wall Integrity In Cryptococcus Neoformans, Stephani S. Martinez Barrera

All Dissertations

Cryptococcus neoformans is a globally distributed fungal pathogen responsible for causing cryptococcal meningitis in immunocompromised individuals. This pathogenic yeast must adapt to changes in temperature upon entering the human host. Septin proteins are conserved filament-forming GTPases that assemble as higher-order complexes at the cell cortex to support cytokinesis and morphogenesis in fungal and animal cells. In C. neoformans, four septin homologs (Cdc3, Cdc10, Cdc11, and Cdc12) assemble at the mother-bud neck, contributing to cytokinesis through poorly understood mechanisms. C. neoformans strains lacking the septins Cdc3 or Cdc12 are viable at 25°C, but fail to proliferate at 37°C, and are …

How Local Interactions Give Rise To Large-Scale Conformational Changes In Proteins: A Molecular Dynamics Study, Shadi A. Badiee

Graduate Theses and Dissertations

Proteins are dynamic entities that undergo conformational changes essential for their biological functions. These structural changes often correspond with chemical events such as lipid interactions or environmental changes like protonation or acidification. Understanding the complex relationship between these chemical perturbations and the resultant mechanical responses is crucial for elucidating protein mechanisms. This dissertation investigates the chemo-mechanical coupling in the conformational dynamics of the bacterial ABC transporter Sav1866 and the impact of protonation on the Influenza virus hemagglutinin HA0. Using molecular dynamics simulations, we explore the conformational landscapes of Sav1866 and HA0. Our study examines how varying lipid compositions affect the …