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Amino Acids, Peptides, and Proteins

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Articles 1 - 30 of 69

Full-Text Articles in Enzymes and Coenzymes

The Concise Guide To Pharmacology 2023/24: Enzymes, Stephen P. H. Alexander, Doriano Fabbro, Eamonn Kelly, Alistair Mathie, John A. Peters, Emma L. Veale, Jane F. Armstrong, Elena Faccenda, Simon D. Harding, James A. Davies, Stephanie Annett, Detlan Boison, Kathryn Elisa Burns, Carmen Dessauer, Jürg Gertsch, Nuala Ann Helsby, Angela A. Izzo, Rennolds Ostrom, Andreas Papapetropoulos, Nigel J. Pyne, Susan Pyne, Tracy Robson, Roland Seifert, Johannes-Peter Stasch, Csaba Szabo, Mario Van Der Stelt, Albert Van Der Vliet, Val Watts, Szu Shen Wong Dec 2023

The Concise Guide To Pharmacology 2023/24: Enzymes, Stephen P. H. Alexander, Doriano Fabbro, Eamonn Kelly, Alistair Mathie, John A. Peters, Emma L. Veale, Jane F. Armstrong, Elena Faccenda, Simon D. Harding, James A. Davies, Stephanie Annett, Detlan Boison, Kathryn Elisa Burns, Carmen Dessauer, Jürg Gertsch, Nuala Ann Helsby, Angela A. Izzo, Rennolds Ostrom, Andreas Papapetropoulos, Nigel J. Pyne, Susan Pyne, Tracy Robson, Roland Seifert, Johannes-Peter Stasch, Csaba Szabo, Mario Van Der Stelt, Albert Van Der Vliet, Val Watts, Szu Shen Wong

Pharmacy Faculty Articles and Research

The Concise Guide to PHARMACOLOGY 2023/24 is the sixth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of approximately 1800 drug targets, and about 6000 interactions with about 3900 ligands. There is an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes almost 500 pages, the material presented is substantially reduced compared to information and links presented on the …


Nanodiscs: A Novel Approach To The Study Of The Methionine Abc Transporter System, Michael T. Winslow Aug 2023

Nanodiscs: A Novel Approach To The Study Of The Methionine Abc Transporter System, Michael T. Winslow

Master's Theses

Membrane transporter proteins play the vital role of moving compounds in and out of the cell and are essential for all living organisms. ATP Binding Cassette (ABC) family transporters function both as importers and exporters in prokaryotes. MetNI is an E. coli Type I ABC transporter responsible for the uptake of methionine into the cytosol from the cell periplasmic space through the cell membrane to maintain intracellular methionine pools. ABC transporters, like other membrane proteins, are most often mechanistically and structurally studied in vitro, solubilized by detergents. However, detergent micelles may affect the conformational changes of membrane proteins relative to …


Leveraging Bio-Inspired Molecules For Cancer Theranostics, Douglas S. Macpherson Feb 2023

Leveraging Bio-Inspired Molecules For Cancer Theranostics, Douglas S. Macpherson

Dissertations, Theses, and Capstone Projects

A variety of molecules can be radiolabeled and delivered to a cancer site for the purposes of diagnostics and therapy. Among the most promising of tumor targeting molecules are peptides and antibodies. These bio-inspired molecules can be designed and synthesized to target and respond to cancer cells based on the properties of those cells. Matrix metalloproteinase (MMP) enzymes are over-expressed by some metastatic cancers, in which they are responsible for the degradation and remodeling of the extracellular matrix. In recent years, MMPs have emerged as promising targets for enzyme-responsive diagnostic probes because oligopeptides can be designed to be selectively hydrolyzed …


High Energy Blue Light Induces Oxidative Stress And Retinal Cell Apoptosis, Jessica Malinsky Jan 2023

High Energy Blue Light Induces Oxidative Stress And Retinal Cell Apoptosis, Jessica Malinsky

Capstone Showcase

Blue light (BL) is a high energy, short wavelength spanning 400 to 500 nm. Found in technological and environmental forms, BL has been shown to induce photochemical damage of the retina by reactive oxygen species (ROS) production. Excess ROS leads to oxidative stress, which disrupts retinal mitochondrial structure and function. As mitochondria amply occupy photoreceptors, they also contribute to oxidative stress due to their selectively significant absorption of BL at 400 to 500 nm. ROS generation that induces oxidative stress subsequently promotes retinal mitochondrial apoptosis. BL filtering and preventative mechanisms have been suggested to improve or repair BL-induced retinal damage, …


Role Of Adenylyl Cyclase Type 7 In Functions Of Bv-2 Microglia, Yawen Hu, Rebecca A. Hill, Masami Yoshimura Dec 2022

Role Of Adenylyl Cyclase Type 7 In Functions Of Bv-2 Microglia, Yawen Hu, Rebecca A. Hill, Masami Yoshimura

School of Medicine Faculty Publications

To assess the role of adenylyl cyclase type 7 (AC7) in microglia’s immune function, we generated AC7 gene knockout (AC7 KO) clones from a mouse microglial cell line, BV-2, using the CRISPR-Cas9 gene editing system. The ability of BV-2 cells to generate cAMP and their innate immune functions were examined in the presence or absence of ethanol. The parental BV-2 cells showed robust cAMP production when stimulated with prostaglandin-E1 (PGE1) and ethanol increased cAMP production in a dose-dependent manner. AC7 KO clones of BV-2 cells showed diminished and ethanol-insensitive cAMP production. The phagocytic activity of the parental BV-2 cells was …


Synthesis And Evaluation Of Anti-Hiv Activity Of Mono- And Di-Substituted Phosphonamidate Conjugates Of Tenofovir, Aaminat Qureshi, Louise A. Ouattara, Naglaa Salem El-Sayed, Amita Verma, Gustavo F. Doncel, Muhammad Iqbal Choudhary, Hina Siddiqui, Keykavous Parang Jul 2022

Synthesis And Evaluation Of Anti-Hiv Activity Of Mono- And Di-Substituted Phosphonamidate Conjugates Of Tenofovir, Aaminat Qureshi, Louise A. Ouattara, Naglaa Salem El-Sayed, Amita Verma, Gustavo F. Doncel, Muhammad Iqbal Choudhary, Hina Siddiqui, Keykavous Parang

Pharmacy Faculty Articles and Research

The activity of nucleoside and nucleotide analogs as antiviral agents requires phosphorylation by endogenous enzymes. Phosphate-substituted analogs have low bioavailability due to the presence of ionizable negatively-charged groups. To circumvent these limitations, several prodrug approaches have been proposed. Herein, we hypothesized that the conjugation or combination of the lipophilic amide bond with nucleotide-based tenofovir (TFV) (1) could improve the anti-HIV activity. During the current study, the hydroxyl group of phosphonates in TFV was conjugated with the amino group of L-alanine, L-leucine, L-valine, and glycine amino acids and other long fatty ester hydrocarbon chains to synthesize 43 derivatives. Several …


Computer Simulations And Network-Based Profiling Of Binding And Allosteric Interactions Of Sars-Cov-2 Spike Variant Complexes And The Host Receptor: Dissecting The Mechanistic Effects Of The Delta And Omicron Mutations, Gennady M. Verkhivker, Steve Agajanian, Ryan Kassab, Keerthi Krishnan Apr 2022

Computer Simulations And Network-Based Profiling Of Binding And Allosteric Interactions Of Sars-Cov-2 Spike Variant Complexes And The Host Receptor: Dissecting The Mechanistic Effects Of The Delta And Omicron Mutations, Gennady M. Verkhivker, Steve Agajanian, Ryan Kassab, Keerthi Krishnan

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this study, we combine all-atom MD simulations and comprehensive mutational scanning of S-RBD complexes with the angiotensin-converting enzyme 2 (ACE2) host receptor in the native form as well as the S-RBD Delta and Omicron variants to (a) examine the differences in the dynamic signatures of the S-RBD complexes and (b) identify the critical binding hotspots and sensitivity of the mutational positions. We also examined the differences in allosteric interactions and communications in the S-RBD complexes for the Delta and Omicron variants. Through the perturbation-based scanning of the allosteric propensities of the SARS-CoV-2 S-RBD residues and dynamics-based network centrality and …


Late-Stage Chemoenzymatic Installation Of Hydroxy-Bearing Allyl Moiety On The Indole Ring Of Tryptophan-Containing Peptides, Nagaraju Mupparapu, Lauren Brewster, Katrina F. Ostrom, Sherif I. Elshahawi Feb 2022

Late-Stage Chemoenzymatic Installation Of Hydroxy-Bearing Allyl Moiety On The Indole Ring Of Tryptophan-Containing Peptides, Nagaraju Mupparapu, Lauren Brewster, Katrina F. Ostrom, Sherif I. Elshahawi

Pharmacy Faculty Articles and Research

The late-stage functionalization of indole- and tryptophan-containing compounds with reactive moieties facilitates downstream diversification and leads to changes in their biological properties. Here, the synthesis of two hydroxy-bearing allyl pyrophosphates is described. A chemoenzymatic method is demonstrated which uses a promiscuous indole prenyltransferase enzyme to install a dual reactive hydroxy-bearing allyl moiety directly on the indole ring of tryptophan-containing peptides. This is the first report of late-stage indole modifications with this reactive group.


Endothelial Nitric Oxide Synthase (Enos) And The Cardiovascular System: In Physiology And In Disease States, N Tran, T Garcia, M Aniqa, S Ali, A Ally, Surya M. Nauli Jan 2022

Endothelial Nitric Oxide Synthase (Enos) And The Cardiovascular System: In Physiology And In Disease States, N Tran, T Garcia, M Aniqa, S Ali, A Ally, Surya M. Nauli

Pharmacy Faculty Articles and Research

Endothelial nitric oxide synthase (eNOS) plays a critical role in regulating and maintaining a healthy cardiovascular system. The importance of eNOS can be emphasized from the genetic polymorphisms of the eNOS gene, uncoupling of eNOS dimerization, and its numerous signaling regulations. The activity of eNOS on the cardiac myocytes, vasculature, and the central nervous system are discussed. The effects of eNOS on the sympathetic autonomic nervous system (SANS) and the parasympathetic autonomic nervous system (PANS), both of which profoundly influence the cardiovascular system, will be elaborated. The relationship between the eNOS protein with cardiovascular autonomic reflexes such as the baroreflex …


Protein Structure And Interaction: The Role Of Aromatic Residues In Protein Structure And Interactions Between Pyridoxine 5'-Phosphate Oxidase/Dopa Decarboxylase, Mohammed H. Al Mughram Jan 2022

Protein Structure And Interaction: The Role Of Aromatic Residues In Protein Structure And Interactions Between Pyridoxine 5'-Phosphate Oxidase/Dopa Decarboxylase, Mohammed H. Al Mughram

Theses and Dissertations

Naturally developed proteins are capable of carrying out a wide variety of molecular functions due to their highly precise three-dimensional structures, which are determined by their genetically encoded sequences of amino acids. A thorough knowledge of protein structures and interactions at the atomic level will enable researchers to get a deep foundational understanding of the molecular interactions and enzymatic processes required for cells, resulting in more effective therapeutic interventions. This dissertation intends to use structural knowledge from solved protein structures for two distinct objectives.

In the first project, we conducted a bioinformatics structural analysis of experimental protein structures using our …


A Review Of Calcineurin Biophysics With Implications For Cardiac Physiology, Ryan B. Williams Dec 2021

A Review Of Calcineurin Biophysics With Implications For Cardiac Physiology, Ryan B. Williams

Theses and Dissertations

Calmodulin is a prevalent calcium sensing protein found in all cells. Three genes exist for calmodulin and all three of these genes encode for the exact same protein sequence. Recently mutations in the amino acid sequence of calmodulin have been identified in living human patients. Thus far, patients harboring these mutations in the calmodulin sequence have only displayed an altered cardiac related phenotype. Calcineurin is involved in many key physiological processes and its activity is regulated by calcium and calmodulin. In order to assess whether or not calcineurin contributes to calmodulinopathy (a pathological state arising from dysfunctional calmodulin), a comprehensive …


The Structural And Functional Role Of Photosensing In Rgs-Lov Proteins, Zaynab Jaber Sep 2021

The Structural And Functional Role Of Photosensing In Rgs-Lov Proteins, Zaynab Jaber

Dissertations, Theses, and Capstone Projects

Light provides organisms with energy and spatiotemporal information. To survive and adapt, organisms have developed the ability to sense light to drive biochemical effects that underlie vision, entrainment of circadian rhythm, stress response, virulence, and many other important molecularly driven responses. Blue-light sensing Light-Oxygen-Voltage (LOV) domains are ubiquitous across multiple kingdoms of life and modulate various physiological events via diverse effector domains. Using a small molecule flavin chromophore, the LOV domain undergoes light-dependent structural changes leading to activation or repression of these catalytic and non-catalytic effectors. In silico analyses of high-throughput genomic sequencing data has led to the marked expansion …


Uplc-Ms/Ms Analysis Of The Michaelis-Menten Kinetics Of Cyp3a-Mediated Midazolam 1′- And 4-Hydroxylation In Rat Brain Microsomes, Devaraj Venkatapura Chandrashekar, Barent Dubois, Reza Mehvar Aug 2021

Uplc-Ms/Ms Analysis Of The Michaelis-Menten Kinetics Of Cyp3a-Mediated Midazolam 1′- And 4-Hydroxylation In Rat Brain Microsomes, Devaraj Venkatapura Chandrashekar, Barent Dubois, Reza Mehvar

Pharmacy Faculty Articles and Research

Midazolam (MDZ) is a short-acting benzodiazepine with rapid onset of action, which is metabolized by CYP3A isoenzymes to two hydroxylated metabolites, 1′-hydroxymidazolam and 4-hydroxymidazolam. The drug is also commonly used as a marker of CYP3A activity in the liver microsomes. However, the kinetics of CYP3A-mediated hydroxylation of MDZ in the brain, which contains much lower CYP content than the liver, have not been reported. In this study, UPLC-MS/MS and metabolic incubation methods were developed and validated for simultaneous measurement of low concentrations of both hydroxylated metabolites of MDZ in brain microsomes. Different concentrations of MDZ (1–500 µM) were incubated with …


Anatomy And Physiology Preparatory Course Textbook (2nd Edition), Carlos Liachovitzky Aug 2021

Anatomy And Physiology Preparatory Course Textbook (2nd Edition), Carlos Liachovitzky

Open Educational Resources

The goal of this preparatory textbook is to give students a chance to become familiar with some terms and some basic concepts they will find later on in the Anatomy and Physiology course, especially during the first few weeks of the course.

Organization and functioning of the human organism are generally presented starting from the simplest building blocks, and then moving into levels of increasing complexity. This textbook follows the same presentation. It begins introducing the concept of homeostasis, then covers the chemical level, and later on a basic introduction to cellular level, organ level, and organ system level. This …


Differential Effect Of Proinflammatory Cytokines On Corneal And Conjunctival Epithelial Cell Mucins And Glycocalyx, Kiumars Shamloo, Priya Mistry, Ashley Barbarino, Christopher Ross, Vishal Jhanji Jun 2021

Differential Effect Of Proinflammatory Cytokines On Corneal And Conjunctival Epithelial Cell Mucins And Glycocalyx, Kiumars Shamloo, Priya Mistry, Ashley Barbarino, Christopher Ross, Vishal Jhanji

Pharmacy Faculty Articles and Research

Purpose: Ocular surface mucins and glycocalyx are critical for providing ocular hydration as well lubrication and repelling pathogens or allergens. Elevated levels of tear proinflammatory cytokines in dry eye may have detrimental effect on mucins and glycocalyx. The present study tested the effect of proinflammatory cytokines IL-6, TNF-α, and IFN-γ on membrane-tethered mucins expression, glycocalyx, and viability of ocular surface epithelial cells.

Methods: Stratified cultures of human corneal and conjunctival epithelial cells were exposed to different concentrations of IL-6, TNF-α, and IFN-γ for 24 hours. The mucins gene and protein expressions were quantified by real-time polymerase chain reaction …


Mediation Of The Uncoupled Enos Pathway Following Oxidative Stress Using Tetrahydrobiopterin And Nitric Oxide Donor Drugs To Restore Tetrahydrobiopterin Concentration, Brianna Munnich Apr 2021

Mediation Of The Uncoupled Enos Pathway Following Oxidative Stress Using Tetrahydrobiopterin And Nitric Oxide Donor Drugs To Restore Tetrahydrobiopterin Concentration, Brianna Munnich

Scholar Week 2016 - present

Presentation Location: Warming House, Olivet Nazarene University

Abstract

The eNOS pathway, found in the endothelium of blood vessels, is a key regulator of nitric oxide levels in the circulatory system. The pathway is controlled through several positive and negative feedback loops [2]. The cofactor tetrahydrobiopterin (BH4) is a major control point in this pathway and under conditions of stress can be reduced into the dihydrobiopterin (BH2) [2,6,7,8,9]. When the reduced form is predominant, the pathway produces reactive oxygen species (ROS) rather than nitric oxide, causing stress and damage to the vessels [6,7,8,9]. In this study, different treatments were studied …


Trna Regulation In Humans: The Cellular Effect Of A Pathological Hars Y454s Mutation, Rosan Kenana Apr 2021

Trna Regulation In Humans: The Cellular Effect Of A Pathological Hars Y454s Mutation, Rosan Kenana

Electronic Thesis and Dissertation Repository

tRNAs are the adapter molecules involved in translating the genetic code into functional protein in a living cell. tRNAs are charged with their cognate amino acids - by aminoacyl-tRNA synthetases (aaRS or ARS) - which are then transferred to a growing peptide in a process called mRNA translation. The efficiency of translation is dependent on the ratio of ARS enzymes to their cognate tRNAs and the availability of correctly amino acylated tRNAs. Disruptions of this process, caused by mutations in ARS genes, in particular, have been linked to complex inherited diseases. USH3B syndrome, a recessively inherited disorder among consanguineous families …


Toxic Effect Of Crotalus Adamanteus Acidic Phospholipase A2 On Mcf-7 Cell Line, Daniel J. Petra Apr 2021

Toxic Effect Of Crotalus Adamanteus Acidic Phospholipase A2 On Mcf-7 Cell Line, Daniel J. Petra

Honors Thesis

We are investigating the effect of Crotalus adamanteus acidic phospholipase A2 on MCF-7 cells using the MTS assay. Understanding these interactions and isolated effects is critical to developing new ways to treat envenomation. By understanding the effects of individual toxins within a whole venom, we are set to better understand the effects of the whole venom and investigate synergistic actions between venom toxins. In this paper, we are quantifying the amount of MCF-7 cell death caused by Crotalus adamanteus phospholipase A2 on MCF-7 using the MTS assay. Analysis of the amount of cells death caused by the phospholipase …


Coevolution, Dynamics And Allostery Conspire In Shaping Cooperative Binding And Signal Transmission Of The Sars-Cov-2 Spike Protein With Human Angiotensin-Converting Enzyme 2, Gennady M. Verkhivker Nov 2020

Coevolution, Dynamics And Allostery Conspire In Shaping Cooperative Binding And Signal Transmission Of The Sars-Cov-2 Spike Protein With Human Angiotensin-Converting Enzyme 2, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Binding to the host receptor is a critical initial step for the coronavirus SARS-CoV-2 spike protein to enter into target cells and trigger virus transmission. A detailed dynamic and energetic view of the binding mechanisms underlying virus entry is not fully understood and the consensus around the molecular origins behind binding preferences of SARS-CoV-2 for binding with the angiotensin-converting enzyme 2 (ACE2) host receptor is yet to be established. In this work, we performed a comprehensive computational investigation in which sequence analysis and modeling of coevolutionary networks are combined with atomistic molecular simulations and comparative binding free energy analysis of …


Determining The Antibacterial Activity And Mode Of Action Of Tirandamycin, Hailey Bouchard Jan 2020

Determining The Antibacterial Activity And Mode Of Action Of Tirandamycin, Hailey Bouchard

CMC Senior Theses

Tirandamycin is a small molecule natural product that has been isolated from various species of marine and terrestrial Streptomyces. The natural product has shown antibacterial activity against an array of Gram-positive and Gram-negative bacteria, showing promise as a pharmaceutical drug. Tirandamycin has 14 known derivatives, many of which have been created synthetically. Some of its derivatives are particularly potent against the high-risk bacteria vancomycin-resistant Enterococcus faecium, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pneumoniae and Escherichia coli. However, the antibacterial potency of these derivatives has not been tested systematically leading to the possibility of discovering more potent …


Pnaktide Attenuates Steatohepatitis And Atherosclerosis By Blocking Na/K-Atpase/Ros Amplification In C57bi6 And Apoe Knockout Mice Fed A Western Diet, K Sodhi, K Srikanthan, P Goguet-Rubio, A Nichols, A Mallick, A Nawab, R Martin, P Shah, M Chaudhry, S Sigdel, M El-Hamdani, J Liu, Z Xie, Nader Abraham, J Shapiro Apr 2019

Pnaktide Attenuates Steatohepatitis And Atherosclerosis By Blocking Na/K-Atpase/Ros Amplification In C57bi6 And Apoe Knockout Mice Fed A Western Diet, K Sodhi, K Srikanthan, P Goguet-Rubio, A Nichols, A Mallick, A Nawab, R Martin, P Shah, M Chaudhry, S Sigdel, M El-Hamdani, J Liu, Z Xie, Nader Abraham, J Shapiro

Nader G. Abraham

We have previously reported that the alpha1 subunit of sodium potassium adenosine triphosphatase (Na/K-ATPase), acts as a receptor and an amplifier for reactive oxygen species, in addition to its distinct pumping function. On this background, we speculated that blockade of Na/K-ATPase-induced ROS amplification with a specific peptide, pNaKtide, might attenuate the development of steatohepatitis. To test this hypothesis, pNaKtide was administered to a murine model of NASH: the C57Bl6 mouse fed a "western" diet containing high amounts of fat and fructose. The administration of pNaKtide reduced obesity as well as hepatic steatosis, inflammation and fibrosis. Of interest, we also noted …


The Pharmabiotic For Phenylketonuria: Development Of A Novel Therapeutic, Chloé Elizabeth Lebegue Apr 2019

The Pharmabiotic For Phenylketonuria: Development Of A Novel Therapeutic, Chloé Elizabeth Lebegue

Senior Theses

Phenylketonuria, now known as phenylalanine hydroxylase (PAH) deficiency, is a genetic disorder of metabolism affecting approximately one in every 15,000 infants born in the United States. Patients have nonfunctional PAH enzyme secondary to one or more genetic mutations. The enzyme deficit results in destructive supraphysiologic blood phenylalanine levels upon consumption of the essential dietary amino acid phenylalanine. Current standards of care mitigate signs and symptoms of the disorder, but do not approach a cure. The methods for creating a prototype pharmabiotic as an innovative treatment strategy for PAH deficiency are described herein.

DNA molecular cloning techniques were utilized to engineer …


Vegf/Neuropilin Signaling In Cancer Stem Cells, Arthur M. Mercurio Mar 2019

Vegf/Neuropilin Signaling In Cancer Stem Cells, Arthur M. Mercurio

Arthur M. Mercurio

The function of vascular endothelial growth factor (VEGF) in cancer extends beyond angiogenesis and vascular permeability. Specifically, VEGF-mediated signaling occurs in tumor cells and this signaling contributes to key aspects of tumorigenesis including the self-renewal and survival of cancer stem cells (CSCs). In addition to VEGF receptor tyrosine kinases, the neuropilins (NRPs) are critical for mediating the effects of VEGF on CSCs, primarily because of their ability to impact the function of growth factor receptors and integrins. VEGF/NRP signaling can regulate the expression and function of key molecules that have been implicated in CSC function including Rho family guanosine triphosphatases …


Toward An Enzyme-Coupled, Bioorthogonal Platform For Methyltransferases: Probing The Specificity Of Methionine Adenosyltransferases, Tyler D. Huber Jan 2019

Toward An Enzyme-Coupled, Bioorthogonal Platform For Methyltransferases: Probing The Specificity Of Methionine Adenosyltransferases, Tyler D. Huber

Theses and Dissertations--Pharmacy

Methyl group transfer from S-adenosyl-l-methionine (AdoMet) to various substrates including DNA, proteins, and natural products (NPs), is accomplished by methyltransferases (MTs). Analogs of AdoMet, bearing an alternative S-alkyl group can be exploited, in the context of an array of wild-type MT-catalyzed reactions, to differentially alkylate DNA, proteins, and NPs. This technology provides a means to elucidate MT targets by the MT-mediated installation of chemoselective handles from AdoMet analogs to biologically relevant molecules and affords researchers a fresh route to diversify NP scaffolds by permitting the differential alkylation of chemical sites vulnerable to NP MTs that are unreactive to …


Characterization Of The Microbial Phosphonate-Activating Pntc Enzymes, Kyle Rice Jan 2019

Characterization Of The Microbial Phosphonate-Activating Pntc Enzymes, Kyle Rice

Theses and Dissertations (Comprehensive)

New strategies are urgently needed to combat infectious diseases in an era of rising antibiotic resistance. Furthermore, an emerging appreciation for the human microbiome’s role in maintaining health motivates discovery of species-specific antibiotics that minimally disrupt our native bacterial communities. Small molecule modifications to bacterial cell surfaces represent a potentially rich source of new targets for next generation antibiotics, as these molecules mediate virulence and evasion of the host immune response. Phosphocholine (PCho) is a rare cell surface modification that contributes to virulence, and modifications with phosphonates like 2-aminoethylphosphonate (AEP) are even more unusual and therefore provide opportunities for species- …


Direct Quantification Of Deubiquitinating Enzyme Activity In Single Intact Cells, Nora Safabakhsh Aug 2018

Direct Quantification Of Deubiquitinating Enzyme Activity In Single Intact Cells, Nora Safabakhsh

LSU Doctoral Dissertations

Challenges in drug efficacy occur during the treatment of most types of cancer due to the heterogeneity of the tumor microenvironment. This has led to the development of personalized medicine. Due to the clinical success of the proteasome inhibitors Bortezomib and Carfilzomib in treatment of multiple myeloma, interest has shifted towards molecularly-targeted chemotherapeutics for ubiquitin-proteasome system (UPS). Deubiquitinating enzymes (DUBs) are an essential part of this pathway which have been found to promote Bortezomib resistance in multiple myeloma patients. Unfortunately, there is a lack of specific, high throughput biochemical assays to characterize DUB activity in patient samples before and after …


Molecular Determinants Of Substrate Specificity In Human Insulin-Degrading Enzyme, Lazaros Stefanidis, Nicholas D. Fusco, Samantha E. Cooper, Jilian E. Smith-Carpenter, Benjamin J. Alper Aug 2018

Molecular Determinants Of Substrate Specificity In Human Insulin-Degrading Enzyme, Lazaros Stefanidis, Nicholas D. Fusco, Samantha E. Cooper, Jilian E. Smith-Carpenter, Benjamin J. Alper

Chemistry & Physics Faculty Publications

Insulin-degrading enzyme (IDE) is a 110 kDa chambered zinc metalloendopeptidase that degrades insulin, amyloid beta, and other intermediate-sized aggregation prone peptides that adopt β-structures. Structural studies of IDE in complex with multiple physiological substrates have suggested a role for hydrophobic and aromatic residues of the IDE active site in substrate binding and catalysis. Here, we examine functional requirements for conserved hydrophobic and aromatic IDE active site residues that are positioned within 4.5 Angstroms of IDE bound insulin B chain and amyloid beta peptides in the reported crystal structures for the respective enzyme-substrate complexes. Charge, size, hydrophobicity, aromaticity, and other functional …


The N-Terminal Methyltransferase Homologs Nrmt1 And Nrmt2 Exhibit Novel Regulation Of Activity Through Heterotrimer Formation., Jon David Faughn Aug 2018

The N-Terminal Methyltransferase Homologs Nrmt1 And Nrmt2 Exhibit Novel Regulation Of Activity Through Heterotrimer Formation., Jon David Faughn

Electronic Theses and Dissertations

Protein, DNA, and RNA methyltransferases have an ever-expanding list of novel substrates and catalytic activities. Even within families and between homologs, it is becoming clear the intricacies of methyltransferase specificity and regulation are far more diverse than originally thought. In addition to specific substrates and distinct methylation levels, methyltransferase activity can be altered through formation of complexes with close homologs. This work involves the N-terminal methyltransferase homologs NRMT1 and NRMT2. NRMT1 is a ubiquitously expressed distributive trimethylase. NRMT2 is a monomethylase expressed at low levels and in a tissue-specific manner. They are both nuclear methyltransferases with overlapping target consensus sequences …


“Do We Know Jack” About Jak? A Closer Look At Jak/Stat Signaling Pathway, Emira Bousoik, Hamidreza Montazeri Aliabadi Jul 2018

“Do We Know Jack” About Jak? A Closer Look At Jak/Stat Signaling Pathway, Emira Bousoik, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

Janus tyrosine kinase (JAK) family of proteins have been identified as crucial proteins in signal transduction initiated by a wide range of membrane receptors. Among the proteins in this family JAK2 has been associated with important downstream proteins, including signal transducers and activators of transcription (STATs), which in turn regulate the expression of a variety of proteins involved in induction or prevention of apoptosis. Therefore, the JAK/STAT signaling axis plays a major role in the proliferation and survival of different cancer cells, and may even be involved in resistance mechanisms against molecularly targeted drugs. Despite extensive research focused on the …


Site-Selective Modification Of Peptides And Proteins Via Organocatalyzed Henry Reaction, Zilma Pereira Muneeswaran May 2018

Site-Selective Modification Of Peptides And Proteins Via Organocatalyzed Henry Reaction, Zilma Pereira Muneeswaran

Seton Hall University Dissertations and Theses (ETDs)

In this research, peptides and protein containing serine on the N-terminus underwent site-selective modification following organocatalyzed bioconjugation that offered an additional functional group. It was shown that transforming the N-terminus serine to an aldehyde allowed site-specific bioconjugation to occur by utilizing the well-known Henry reaction. This method also grants a safer pathway for bioconjugation utilizing “green-chemistry” and biocompatible conditions. Amino acids and amino acid derived organocatalysts were utilized in the Henry reaction resulting in yields of up to 86 % conversion. Promising preliminary results were achieved in this research using peptides and myoglobin as the bioconjugation targets. Further investigation to …