Amino Acids, Peptides, and Proteins Commons^™

Synthesis And Biochemical Activities Of Antiproliferative Amino Acid And Phosphate Derivatives Of Microtubule-Disrupting Beta-Lactam Combretastatins, Niamh M. O'Boyle, Lisa M. Greene, Niall O. Keely, Shu Wang, Tadhg S. Cotter, Daniela M. Zisterer, Mary J. Meegan

Articles

The synthesis and biochemical activities of novel water-soluble β-lactam analogues of combretastatin A-4 are described. The first series of compounds investigated, β-lactam phosphate esters 7a, 8a and 9a, exhibited potent antiproliferative activity and caused microtubule disruption in human breast carcinoma-derived MCF-7 cells. They did not inhibit tubulin polymerisation in vitro, indicating that biotransformation was necessary for their antiproliferative and tubulin binding effects in MCF-7 cells. The second series of compounds, β-lactam amino acid amides (including 10k and 11l) displayed potent antiproliferative activity in MCF-7 cells, disrupted microtubules in MCF-7 cells and also inhibited the polymerisation of …

Revisiting The Fundamentals In The Design And Control Of Nanoparticulate Colloids In The Frame Of Soft Chemistry, Vuk Uskoković

Pharmacy Faculty Articles and Research

This review presents thoughts on some of the fundamental features of conceptual models applied in the design of fine particles in the frames of colloid and soft chemistry. A special emphasis is placed on the limitations of these models, an acknowledgment of which is vital in improving their intricacy and effectiveness in predicting the outcomes of the corresponding experimental settings. Thermodynamics of self-assembly phenomena illustrated on the examples of protein assembly and micellization is analyzed in relation to the previously elaborated thesis that each self-assembly in reality presents a co-assembly, since it implies a mutual reorganization of the assembling system …

Self-Assembled Surfactant Cyclic Peptide Nanostructures As Stabilizing Agents, Dindyal Mandal, Rakesh Tiwari, Amir Nasrolahi Shirazi, Donghoon Oh, Guofeng Ye, Antara Banerjee, Arpita Yadav, Keykavous Parang

Pharmacy Faculty Articles and Research

A number of cyclic peptides including [FR](4), [FK](4), [WK](5), [CR](4), [AK](4), and [WR](n) (n = 3-5) containing L-amino acids were produced using solid-phase peptide synthesis. We hypothesized that an optimal balance of hydrophobicity and charge could generate self-assembled nanostructures in aqueous solution by intramolecular and/or intermolecular interactions. Among all the designed peptides, [WR](n) (n = 3-5) generated self-assembled vesicle-like nanostructures at room temperature as shown by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and/or dynamic light scattering (DLS). This class of peptides represents the first report of surfactant-like cyclic peptides that self-assemble into nanostructures. A plausible mechanistic insight into …

Chikungunya Virus Infection Results In Higher And Persistent Viral Replication In Aged Rhesus Macaques Due To Defects In Anti-Viral Immunity, Ilhem Messaoudi, Jennifer Totonchy, Thomas Totonchy, Craig N. Kreklywich, Kristen Haberthur, Laura Springgay, James D. Brien, Michael S. Diamond, Victor R. Defilippis, Daniel N. Streblow

Pharmacy Faculty Articles and Research

Chikungunya virus (CHIKV) is a re-emerging mosquito-borne Alphavirus that causes a clinical disease involving fever, myalgia, nausea and rash. The distinguishing feature of CHIKV infection is the severe debilitating poly-arthralgia that may persist for several months after viral clearance. Since its re-emergence in 2004, CHIKV has spread from the Indian Ocean region to new locations including metropolitan Europe, Japan, and even the United States. The risk of importing CHIKV to new areas of the world is increasing due to high levels of viremia in infected individuals as well as the recent adaptation of the virus to the mosquito species Aedes …

Aberrant Proliferation In Cxcr7+ Endothelial Cells Via Degradation Of The Retinoblastoma Protein, Jennifer Totonchy, Jessica M. Osborn, Sara Botto, Lisa Clepper, Ashlee V. Moses

Pharmacy Faculty Articles and Research

Angiogenesis is a critical factor in the growth and dissemination of solid tumors. Indeed, tumor vasculature is abnormal and contributes to the development and spread of malignancies by creating a hostile microenvironment. The alternative SDF-1/CXCL12 receptor, CXCR7, is frequently and specifically expressed in tumor-associated vessels. In this study, we examine the role of endothelium-expressed CXCR7 in tumor vascular dysfunction by specifically examining the contribution of CXCR7 to endothelial cell (EC) proliferation. We demonstrate that CXCR7 expression is sufficient to drive post-confluent growth in EC cultures. Further, we provide a novel mechanism for CXCR7-mediated proliferation via proteasomal degradation of the tumor …

Novel Therapy For Nicotine Addiction In Alcohol Dependent Rats, Bethany Ann Stennett

UNF Graduate Theses and Dissertations

The co-dependence of nicotine and alcohol addiction occurs at high rates, complicates treatment, and is often associated with significant morbidity and mortality. Treatment options of alcohol and tobacco co-dependence are limited. Currently, there are drugs available for nicotine dependence or alcohol dependence. However, there are no therapeutic drugs available on the market for the co-dependence of nicotine and alcohol. Therefore, and important opportunity of new therapeutic options and drug development has presented itself. NT69L, a non-selective neurotensin (NT) agonist, provides a potential novel therapy for nicotine addiction in alcoholics by interacting with the common neurotransmitter circuits supporting the rewarding process …

The Influence Of A Coiled-Coil Isoleucine Zipper On The Trimerization And Endosomolytic Activity Of The E5-Tat-Mcherry Protein, Valerie Nickel

Honors Theses

The E5-TAT-mCherry protein is designed to initiate cellular uptake through endocytosis and react to the acidification of the endosomes by causing membrane lysis and cytosolic delivery. The cell penetrating peptide TAT from the HIV transcription activator binds to the cellular membrane and transports attached or coincubated cargo into the cell through endocytosis. E5 is a derivative of the fusogenic peptide HA2 from the influenza hemagglutinin protein and reacts to the acidification of the endosomal lumen by inserting into the membrane and increasing membrane permeability. The attached red fluorescent protein mCherry serves as a convenient biological probe for cell based assays. …

(R)-Β-Lysine Modified Elongation Factor P Functions In Translation Elongation, Tammy J. Bullwinkle, S. Betty Zou, Andrei Rajkovic, Steven J. Hersch, Sara Elgamal, Nathaniel Robinson, David Smil, Yuri Bolshan, William Wiley Navarre, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Post-translational modification of bacterial elongation factor P (EF-P) with (R)-β-lysine at a conserved lysine residue activates the protein in vivo and increases puromycin reactivity of the ribosome in vitro. The additional hydroxylation of EF-P at the same lysine residue by the YfcM protein has also recently been described. The roles of modified and unmodified EF-P during different steps in translation, and how this correlates to its physiological role in the cell, have recently been linked to the synthesis of polyproline stretches in proteins. Polysome analysis indicated that EF-P functions in translation elongation, rather than initiation as proposed previously. This was …

Selection Of Trna Charging Quality Control Mechanisms That Increase Mistranslation Of The Genetic Code, Srujana S. Yadavalli, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Mistranslation can follow two events during protein synthesis: production of non-cognate amino acid:transfer RNA (tRNA) pairs by aminoacyl-tRNA synthetases (aaRSs) and inaccurate selection of aminoacyl-tRNAs by the ribosome. Many aaRSs actively edit non-cognate amino acids, but editing mechanisms are not evolutionarily conserved, and their physiological significance remains unclear. To address the connection between aaRSs and mistranslation, the evolutionary divergence of tyrosine editing by phenylalanyl-tRNA synthetase (PheRS) was used as a model. Certain PheRSs are naturally error prone, most notably a Mycoplasma example that displayed a low level of specificity consistent with elevated mistranslation of the proteome. Mycoplasma PheRS was found …

Mrp4 Is A Crucial Regulator Of Testosterone Biosynthesis, Jessica Ann Morgan

Theses and Dissertations (ETD)

The physiological role of multidrug resistance protein 4 (Mrp4) in the testes is unknown. It was discovered that Mrp4 is expressed primarily in mouse and human Leydig cells; however, there is no current evidence that Mrp4 regulates testosterone biosynthesis. The role of Mrp4 was investigated in Leydig cells where testosterone production is regulated by cAMP, an intracellular second messenger formed when the luteinizing hormone (LH) receptor (Lhr) is activated. As Mrp4 regulates cAMP, we compared testosterone levels in our Mrp4 WT and KO mice. Prepubertal KO mice had significantly reduced testicular testosterone, impaired gametogenesis, and disrupted cAMP homeostasis, resulting in …

Experimental And Computational Analysis Of The Structure And Dynamics Of Intrinsically Disordered Proteins, Elio Anthony Cino

Electronic Thesis and Dissertation Repository

Intrinsically disordered proteins (IDPs) are abundant in cells and have central roles in

protein-protein interaction networks. Many are involved in cancer, aging and

neurodegenerative diseases. The structure and dynamics of IDPs is intimately related to their

interactions with binding partners. Because IDPs are inherently flexible and do not have a

single conformation, conventional methods and conditions for determining structure and

dynamics of globular proteins may not be directly applicable. Nuclear magnetic resonance

(NMR) spectroscopy is one of the primary techniques characterizing the structures and

dynamics of IDPs, but one cannot rely solely on NMR data. A primary aim of this …

The Role Of The Yxxφ Motif In Cd82 Trafficking And Function, Mekel Marie Richardson

Theses and Dissertations (ETD)

CD82, a tetraspanin, is a tumor metastasis suppressor. Tetraspanins are membrane spanning proteins that play critical roles in diverse biological and pathological processes, e.g., the regulation of cancer metastasis. CD82 is ubiquitously expressed in various types of tissues, but its expression becomes down-regulated or lost in a majority of metastatic tumors. It inhibits tumor metastasis without affecting primary tumor growth. Cancer patients whose tumors contain CD82 exhibit minimal metastasis. We know that CD82 functions as a tumor metastasis suppressor but the mechanism by which this occurs is largely unknown. CD82 can be found on the plasma membrane as well as …

Obtaining A Pure Protein Using An Elp-Tagged Tev Protease, Teisha L. Mullins

Undergraduate Research Posters 2012

We present here use of GLGVP for tagging and purifying a gadolinium binding protein domain.

Understanding The Structure Of High Density Lipoprotein, Dmitriy Parshakov, Kayla T. Tran

Undergraduate Research Posters 2012

The high-density lipoprotein (HDL), the carrier of ‘good cholesterol’, transports cholesterol from periphery cells to liver for catabolism, a process termed reverse cholesterol transport. In this project we focused on obtaining and characterizing HDL particles.

Borrelia Burgdorferi Cp32 Bpab Modulates Expression Of The Prophage Nucp Nuclease And Ssbp Single-Stranded Dna-Binding Protein, Alicia M. Chenail, Brandon L. Jutras, Claire A. Adams, Logan H. Burns, Amy Bowman, Ashutosh Verma, Brian Stevenson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The Borrelia burgdorferi BpaB proteins of the spirochete's ubiquitous cp32 prophages are DNA-binding proteins, required both for maintenance of the bacteriophage episomes and for transcriptional regulation of the cp32 erp operons. Through use of DNase I footprinting, we demonstrate that BpaB binds the erp operator initially at the sequence 5′-TTATA-3′. Electrophoretic mobility shift assays indicated that BpaB also binds with high affinity to sites located in the 5′ noncoding regions of two additional cp32 genes. Characterization of the proteins encoded by those genes indicated that they are a single-stranded DNA-binding protein and a nuclease, which we named SsbP and NucP, …

Identification Of The Functional Binding Pocket For Compounds Targeting Small-Conductance Ca2+-Activated Potassium Channels, Miao Zhang, John M. Pascal, Marcel Schumann, Roger S. Armen, Ji-Fang Zhang

Pharmacy Faculty Articles and Research

Small- and intermediate-conductance Ca2+-activated potassium channels, activated by Ca2+-bound calmodulin, play an important role in regulating membrane excitability. These channels are also linked to clinical abnormalities. A tremendous amount of effort has been devoted to developing small molecule compounds targeting these channels. However, these compounds often suffer from low potency and lack of selectivity, hindering their potentials for clinical use. A key contributing factor is the lack of knowledge of the binding site(s) for these compounds. Here we demonstrate by X-ray crystallography that the binding pocket for the compounds of the 1-EBIO class is located at the calmodulin-channel interface. We …

Taking Aim At The Start Of Translation, Medha Raina, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

No abstract provided.

A Pseudo-Trna Modulates Antibiotic Resistance In Bacillus Cereus, Theresa E. Rogers, Sandro F. Ataide, Kiley Dare, Assaf Katz, Stephanie Seveau, Hervé Roy, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Bacterial genomic islands are often flanked by tRNA genes, which act as sites for the integration of foreign DNA into the host chromosome. For example, Bacillus cereus ATCC14579 contains a pathogenicity island flanked by a predicted pseudo-tRNA, tRNAOther, which does not function in translation. Deletion of tRNAOther led to significant changes in cell wall morphology and antibiotic resistance and was accompanied by changes in the expression of numerous genes involved in oxidative stress responses, several of which contain significant complementarities to sequences surrounding tRNAOther. This suggested that tRNAOther might be expressed as part of a larger RNA, and RACE analysis …

Regulation Of Lipogenesis By Cyclin-Dependent Kinase 8-Mediated Control Of Srebp-1., Xiaoping Zhao, Daorong Feng, Qun Wang, Arian Abdulla, Xiao-Jun Xie, Jie Zhou, Yan Sun, Ellen S Yang, Lu-Ping Liu, Bhavapriya Vaitheesvaran, Lauren Bridges, Irwin J Kurland, Randy Strich, Jian-Quan Ni, Chenguang Wang, Johan Ericsson, Jeffrey E Pessin, Jun-Yuan Ji, Fajun Yang

Department of Cancer Biology Faculty Papers

Altered lipid metabolism underlies several major human diseases, including obesity and type 2 diabetes. However, lipid metabolism pathophysiology remains poorly understood at the molecular level. Insulin is the primary stimulator of hepatic lipogenesis through activation of the SREBP-1c transcription factor. Here we identified cyclin-dependent kinase 8 (CDK8) and its regulatory partner cyclin C (CycC) as negative regulators of the lipogenic pathway in Drosophila, mammalian hepatocytes, and mouse liver. The inhibitory effect of CDK8 and CycC on de novo lipogenesis was mediated through CDK8 phosphorylation of nuclear SREBP-1c at a conserved threonine residue. Phosphorylation by CDK8 enhanced SREBP-1c ubiquitination and protein …

Identification Of Persistent Long Range Interactions In GA95 And GB95 Through Thermal Unfolding Simulations, Milen Redai Tesfamariam

Chemistry & Biochemistry Theses & Dissertations

For over five decades, different experiments have been performed to research how proteins attain their native three dimensional structures. However, the folding problem continues to be a puzzle in modern science. The design of two proteins that have maximal sequence identity but different folds and functions is one method that is being used to study the relationship between protein structure and amino acid sequence. In particular, mutant proteins of Streptococcus protein G, G_A and G_B, have 95% sequence identity and a 3a helix fold and β4/a fold, respectively. Molecular dynamics simulations of G_A95 …