Amino Acids, Peptides, and Proteins Commons^™

Syntheses Of Precursors To Fluorine-18 Labeled Pet Imaging Agents, Lindsay B. Boling

Chancellor’s Honors Program Projects

No abstract provided.

Mamba Juice: Expression Of Exogenous Mambalgin Peptide Using The Pgapzα Vector System, Lydia Studdard, Kristin Vanmouwerik, Merhawi Yigzaw, Reza Alavi

Georgia State Undergraduate Research Conference

No abstract provided.

Sample Limited Characterization Of A Novel Disulfide- Rich Venom Peptide Toxin From Terebrid Marine Snail Terebra Variegata, Prachi Anand, Alexandre Grigoryan, Mohammed H. Bhuiyan, Beatrix Ueberheide, Victoria Russell, Jose Quiñonez, Patrick Moy, Brian T. Chait, Sébastien F. Poget, Mandë Holford

Publications and Research

Disulfide-rich peptide toxins found in the secretions of venomous organisms such as snakes, spiders, scorpions, leeches, and marine snails are highly efficient and effective tools for novel therapeutic drug development. Venom peptide toxins have been used extensively to characterize ion channels in the nervous system and platelet aggregation in haemostatic systems. A significant hurdle in characterizing disulfide-rich peptide toxins from venomous animals is obtaining significant quantities needed for sequence and structural analyses. Presented here is a strategy for the structural characterization of venom peptide toxins from sample limited (4 ng) specimens via direct mass spectrometry sequencing, chemical synthesis and NMR …

Mechanism Underlying Ikk Activation Mediated By The Linear Ubiquitin Chain Assembly Complex (Lubac), Hiroaki Fujita, Simin Rahighi, Mariko Akita, Ryuichi Kato, Yoshiteru Sasaki, Soichi Wakatsuki, Kazuhiro Iwai

Pharmacy Faculty Articles and Research

The linear ubiquitin chain assembly complex (LUBAC) ligase, consisting of HOIL-1L, HOIP, and SHARPIN, specifically generates linear polyubiquitin chains. LUBAC-mediated linear polyubiquitination has been implicated in NF-κB activation. NEMO, a component of the IκB kinase (IKK) complex, is a substrate of LUBAC, but the precise molecular mechanism underlying linear chain-mediated NF-κB activation has not been fully elucidated. Here, we demonstrate that linearly polyubiquitinated NEMO activates IKK more potently than unanchored linear chains. In mutational analyses based on the crystal structure of the complex between the HOIP NZF1 and NEMO CC2-LZ domains, which are involved in the HOIP-NEMO interaction, NEMO mutations …

The Development Of A Synthetic Route For A Disubsitituted Diphenylacetylene And Its Conformational Characteristics Upon Coordination To Tungsten: A Prospect For Beta-Sheet Studies, Francis Herman

Senior Theses and Projects

The study of β-sheet mimetics represents an important step in understanding the structural and function of β-sheets. The purpose of this report was to develop a β-sheet mimetic through a diphenylacetylene backbone, coordinate the complex to tungsten and determine the structural and conformational characteristics of the complex. In order to characterize the different compounds ESI-MS, ¹HNMR, COSY NMR, NOESY NMR, and ROESY NMR were employed. The diphenylacetylene backbone contained two phenyl substituents with a peptide chain of two amino acids. The β-sheet mimetic 1 was successfully synthesized utilizing peptide coupling reactions and a Sonogashira coupling reaction. Previous research by …

Covalent Protein Adduction Of Nitrogen Mustards And Related Compounds, Vanessa R. Thompson

FIU Electronic Theses and Dissertations

Chemical warfare agents continue to pose a global threat despite the efforts of the international community to prohibit their use in warfare. For this reason, improvement in the detection of these compounds remains of forensic interest. Protein adducts formed by the covalent modification of an electrophilic xenobiotic and a nucleophilic amino acid may provide a biomarker of exposure that is stable and specific to compounds of interest (such as chemical warfare agents), and have the capability to extend the window of detection further than the parent compound or circulating metabolites. This research investigated the formation of protein adducts of the …

Responsive Polymers For Biosensing And Protein Delivery, Molla R. Islam, Yongfeng Gao, Xue Li, Michael J. Serpe

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

In this feature article, we review some of the most recent advances in the field of materials chemistry for biosensing, disease diagnostics, and drug delivery. Our recent work on the development of responsive polymer-based platforms for biosensing and drug delivery will also be highlighted. This feature article is meant to outline the breadth of the utility of polymer-based materials for select applications, as well as their enormous potential impact on future technologies.

The Abcs Of The Ribosome, Kurt Fredrick, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

An ABC protein that binds the ribosomal exit site suggests a new mechanism for direct regulation of translation in response to changing ATP levels in the cell.

Protein Binding Drug-Drug Interaction Between Warfarin And Tizoxanide In Human Plasma, Eduard Mullokandov, Jennifer Ahn, Andrew Szalkiewicz, Mariana Babayeva

Touro College of Pharmacy (New York) Publications and Research

The goal of the in vitro research was to evaluate the potential for inhibition of warfarin protein binding by tizoxanide. Warfarin was of particular interest for the present investigation because it has been shown to be highly bound to plasma proteins and is a narrow therapeutic index drug. Tizoxanide is an active metabolite of an anti-infective prodrug nitazoxanide and also highly protein-bound medication. Both drugs are expected to be co-administered clinically. Protein binding of warfarin was investigated using a centrifugal ultrafiltration technique. Co-administration of tizoxanide significantly inhibited protein binding of warfarin for all concentrations tested. Tizoxanide increased free fraction (fu) …

Alteration Of Host Cell Ubiquitination By The Intracellular Bacterial Pathogen Coxiella Burnetii, Lindsay Pritchett, Daniel E. Voth

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The intracellular bacterial agent of Q fever, Coxiella burnetii, replicates within a phagolysosomelike parasitophorous vacuole (PV) in human macrophages and delivers effector proteins to the host cytosol via a Dot/Icm type IV secretion system (T4SS). The T4SS effectors are critical for PV formation and prevention of host cell death that allows sufficient time for bacterial replication. Recruitment of ubiquitin-related components to the C. burnetii PV is also predicted to be involved in PV formation and bacterial replication and is likely controlled by effector proteins. In this study, we assessed the role of the Dot/Icm T4SS in regulating ubiquitination by comparing …

Effect Of Chronic Angiotensin Ii Infusion On Plasma Tnfalpha And Il 6 Levels In Adiponectin Deficient Mice, Alexis O'Brien, Minnette Smith, Jaya Pamidimukkala

College of Osteopathic Medicine (TUN) Publications and Research

Chronic low grade inflammation plays an integral part in the development of many types of cardiovascular diseases. Adipose tissue is a well known source of many proinflammatory mediators. Adiponectin (APN) is one of the few proteins secreted by the adipose tissue that is known to have anti-inflammatory properties. Our research goal is to understand if APN deficiency contributes to a proinflammatory milieu especially when provided with an appropriate stimulus. Angiotensin II (ANGII) is a well known prohypertensive agent. Recently, ANGII has emerged as a growth factor and stimulator of proinflammatory cytokine expression in cardiovascular & renal tissue. The present study …

Involvement Of Sigma-1 Receptors In The Antidepressant-Like Effects Of Dextromethorphan, Linda Nguyen, Matthew J. Robson, Jason R. Healy, Anna L. Scandinaro, Rae Reiko Matsumoto

Faculty Publications & Research of the TUC College of Pharmacy

Dextromethorphan is an antitussive with a high margin of safety that has been hypothesized to display rapid-acting antidepressant activity based on pharmacodynamic similarities to the N-methyl-D-aspartate (NMDA) receptor antagonist ketamine. In addition to binding to NMDA receptors, dextromethorphan binds to sigma-1 (s1) receptors, which are believed to be protein targets for a potential new class of antidepressant medications. The purpose of this study was to determine whether dextromethorphan elicits antidepressant-like effects and the involvement of s1 receptors in mediating its antidepressant-like actions. The antidepressant-like effects of dextromethorphan were assessed in male, Swiss Webster mice using the forced swim test. Next, …

Cardiac Troponin Assessment Following Atrial Fibrillation Ablation: Implications For Chest Pain Evaluation, Jason C. Rubenstein, Jason T. Jacobson, Jeffrey J. Goldberger, Rod Passman, Alan H. Kadish, Michael H. Kim

Office of the President Publications and Research

Background: The range of elevation of troponin I (tI) that is within expected limits from left atrial radiofrequency ablation for atrial fibrillation (AF) is not well described, though such information may be of clinical value.

Objectives: Identify the expected range of tI values post-atrial fibrillation (AF) ablation.

Methods: 31 patients undergoing AF ablation had a single tI level drawn the day following the procedure. Clinical variables were also collected, such as ablation type and radiofrequency (RF) time.

Results: Paroxysmal AF was present in 23 patients, and 8 had chronic AF. The average RF time was 2627.8 …

Beta-Alanine Suppresses Malignant Breast Epithelial Cell Aggressiveness Through Alterations In Metabolism And Cellular Acidity In Vitro, Roger A. Vaughan, Nicholas P. Gannon, Randi Garcia-Smith, Yamhilette Licon-Munoz, Miguel A. Barberena, Marco Bisoffi, Kristina A. Trujillo

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background: Deregulated energetics is a property of most cancer cells. This phenomenon, known as the Warburg Effect or aerobic glycolysis, is characterized by increased glucose uptake, lactate export and extracellular acidification, even in the presence of oxygen. beta-alanine is a non-essential amino acid that has previously been shown to be metabolized into carnosine, which functions as an intracellular buffer. Because of this buffering capacity, we investigated the effects of beta-alanine on the metabolic cancerous phenotype.

Methods: Non-malignant MCF-10a and malignant MCF-7 breast epithelial cells were treated with beta-alanine at 100 mM for 24 hours. Aerobic glycolysis was quantified …

Hydropathic Interactions And Protein Structure: Utilizing The Hint Force Field In Structure Prediction And Protein‐Protein Docking., Mostafa H. Ahmed

Theses and Dissertations

Protein structure predication is a field of computational molecular modeling with an enormous potential for improvement. Side-chain geometry prediction is a critical component of this process that is crucial for computational protein structure predication as well as crystallographers in refining experimentally determined protein crystal structures. The cornerstone of side-chain geometry prediction are side-chain rotamer libraries, usually obtained through exhaustive statistical analysis of existing protein structures. Little is known, however, about the driving forces leading to the preference or suitability of one rotamer over another. Construction of 3D hydropathic interaction maps for nearly 30,000 tyrosines extracted from the PDB reveals their …

Computational Modeling Of Allosteric Regulation In The Hsp90 Chaperones: A Statistical Ensemble Analysis Of Protein Structure Networks And Allosteric Communications, Kristin Blacklock, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

A fundamental role of the Hsp90 chaperone in regulating functional activity of diverse protein clients is essential for the integrity of signaling networks. In this work we have combined biophysical simulations of the Hsp90 crystal structures with the protein structure network analysis to characterize the statistical ensemble of allosteric interaction networks and communication pathways in the Hsp90 chaperones. We have found that principal structurally stable communities could be preserved during dynamic changes in the conformational ensemble. The dominant contribution of the inter-domain rigidity to the interaction networks has emerged as a common factor responsible for the thermodynamic stability of the …

Cyclic Peptide-Capped Gold Nanoparticles For Enhanced Sirna Delivery, Amir Nasrolahi Shirazi, Karissa L. Paquin, Niall G. Howlett, Dindyal Mandal, Keykavous Parang

Pharmacy Faculty Articles and Research

Previously, we have reported the synthesis of a homochiral L-cyclic peptide [WR]5 and its use for delivery of anti-HIV drugs and biomolecules. A physical mixture of HAuCl4 and the peptide generated peptide-capped gold nanoparticles. Here, [WR]5 and [WR]5-AuNPs were tested for their efficiency to deliver a small interfering RNA molecule (siRNA) in human cervix adenocarcinoma (HeLa) cells. Flow cytometry investigation revealed that the intracellular uptake of a fluorescence-labeled non-targeting siRNA (200 nM) was enhanced in the presence of [WR]5 and [WR]5-AuNPs by 2- and 3.8-fold when compared with that of siRNA alone after 24 h incubation. Comparative toxicity results showed …

Carbocyclodipeptides As Modified Nucleosides: Synthesis And Anti- Hiv Activities, Bhupender S. Chhikara, M. Sudershan Rao, V. Kameshwara Rao, Anil Kumar, Karen W. Buckheit, Robert W. Buckheit Jr., Keykavous Parang

Pharmacy Faculty Articles and Research

A new class of nucleoside analogues were synthesized using cyclic dipeptides and modified 2′-deoxyfuranoribose sugars to introduce flexibility by peptides in place of common nucleoside bases and to determine their biological properties. The synthesis was carried out by coupling of a protected ribose sugar with synthesized dipeptides in the presence of hexamethyldisilazane and trimethylsilyltriflate. The final products were characterized by NMR and high-resolution MS-TOF spectroscopy. The compounds were evaluated for anti-HIV activities. 1-(4-Azido-5-(hydroxymethyl)tetrahydrofuran-2-yl)-3,6-diisopropylpiperazine-2,5-dione (compound 14) containing 3- and 6-isopropyl groups in the base and 3′-azide (EC50 = 1.96 μmol/L) was the most potent compound among all of the synthesized analogs.

Non-Raft Ac2 Defines A Camp Signaling Compartment That Selectively Regulates Il-6 Expression In Airway Smooth Muscle Cells, Amy S. Bogard, Anna V. Birg, Rennolds S. Ostrom

Pharmacy Faculty Articles and Research

Adenylyl cyclase (AC) isoforms differ in their tissue distribution, cellular localization, regulation, and protein interactions. Most cell types express multiple AC isoforms. We hypothesized that cAMP produced by different AC isoforms regulates unique cellular responses in human bronchial smooth muscle cells (BSMC). Overexpression of AC2, AC3, or AC6 had distinct effects on forskolin (Fsk)-induced expression of a number of known cAMP-responsive genes. These data show that different AC isoforms can differentially regulate gene expression. Most notable, overexpression and activation of AC2 enhanced interleukin 6 (IL-6) expression, but overexpression of AC3 or AC6 had no effect. IL-6 production by BSMC was …

Self-Assembly Of Peptides To Nanostructures, Dindyal Mandal, Amir Nasrolahi Shirazi, Keykavous Parang

Pharmacy Faculty Articles and Research

The formation of well-ordered nanostructures through self-assembly of diverse organic and inorganic building blocks has drawn much attention owing to their potential applications in biology and chemistry. Among all organic building blocks, peptides are one of the most promising platforms due to their biocompatibility, chemical diversity, and resemblance with proteins. Inspired from the protein assembly in biological systems, various self-assembled peptide structures have been constructed using several amino acids and sequences. This review focuses on this emerging area, the recent advances in peptide self-assembly, and formation of different nanostructures, such as tubular, fibers, vesicles, spherical, and rod coil structures. While …

A Potential Mechanism For Extracellular Matrix Induction Of Breast Cancer Cell Normality, Robert D. Bruno, Gilbert H. Smith

Medical Diagnostics & Translational Sciences Faculty Publications

Extracellular matrix proteins from embryonic mesenchyme have a normalizing effect on cancer cells in vitro and slow tumor growth in vivo. This concept is suggestive of a new method for controlling the growth and spread of existing cancer cells in situ and indicates the possibility that extracellular proteins and/or embryonic mesenchymal fibroblasts may represent a fertile subject for study of new anti-cancer treatments.

Leptin Regulates Cd16 Expression On Human Monocytes In A Sex-Specific Manner, Joseph G. Cannon, Gyanendra Sharma, Gloria Sloan, Christiana Dimitropoulou, R. Randall Baker, Andrew Mazzoli, Barbara Kraj, Anthony Mulloy, Miriam Cortez-Cooper

Medical Diagnostics & Translational Sciences Faculty Publications

Fat mass is linked mechanistically to the cardiovascular system through leptin, a 16 kDa protein produced primarily by adipocytes. In addition to increasing blood pressure via hypothalamic-sympathetic pathways, leptin stimulates monocyte migration, cytokine secretion, and other functions that contribute to atherosclerotic plaque development. These functions are also characteristics of CD16-positive monocytes that have been implicated in the clinical progression of atherosclerosis. This investigation sought to determine if leptin promoted the development of such CD16-positive monocytes. Cells from 45 healthy men and women with age ranging from 20 to 59 years were analyzed. Circulating numbers of CD14++16++ monocytes, which are primary …

Cxcr7 Expression Disrupts Endothelial Cell Homeostasis And Causes Ligand-Dependent Invasion, Jennifer Totonchy, Lisa Clepper, Kevin G. Phillips, Owen J. T. Mccarty, Ashlee V. Moses

Pharmacy Faculty Articles and Research

The homeostatic function of endothelial cells (EC ) is critical for a number of physiological processes including vascular integrity, immunity, and wound healing. Indeed, vascular abnormalities resulting from EC dysfunction contribute to the development and spread of malignancies. The alternative SDF-1/CXCL12 receptor CXCR7 is frequently and specifically highly expressed in tumor-associated vessels. In this study, we investigate whether CXCR7 contributes to vascular dysfunction by specifically examining the effect of CXCR7 expression on EC barrier function and motility. We demonstrate that CXCR7 expression in EC results in redistribution of CD31/PECAM-1 and loss of contact inhibition. Moreover, CXCR7+ EC are deficient in …

Amphiphilic Triazolyl Peptides: Synthesis And Evaluation As Nanostructures, Naser Sayeh, Amir Nasrolahi Shirazi, Donghoon Oh, Jiadong Sun, David Rowley, Antara Banerjee, Arpita Yadav, Rakesh Tiwari, Keykavous Parang

Pharmacy Faculty Articles and Research

A new class of amphiphilic triazolyl peptides was designed and synthesized from peptide-based building blocks containing alkyne and azide functional groups namely linear (W(pG))3, cyclic[W(pG)]3, and Ac-K(N3)R-NH2,where W, R, K, and pG represent tryptophan, arginine, lysine, and propargylglycine residues, respectively. The linear (W(pG))3 and cyclic [W(pG)]3 peptides containing alkyne residues were conjugated with Ac-K(N3)R-NH2 functionalized with azide group through click chemistry in the presence of CuSO4.5H2O, Cu (powder), sodium ascorbate, and N,N-disopropylethylamine in methanol:water to afford amphiphilic triazolyl linear-linear (WG(triazole-KR-NH2))3 and cyclic-linear [WG(triazole-KR-NH2)]3 peptides, respectively. The secondary structures of both peptides were similar to a distorted α-helix as shown by …

Allosteric Regulation Of The Hsp90 Dynamics And Stability By Client Recruiter Cochaperones: Protein Structure Network Modeling, Kristin Blacklock, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

The fundamental role of the Hsp90 chaperone in supporting functional activity of diverse protein clients is anchored by specific cochaperones. A family of immune sensing client proteins is delivered to the Hsp90 system with the aid of cochaperones Sgt1 and Rar1 that act cooperatively with Hsp90 to form allosterically regulated dynamic complexes. In this work, functional dynamics and protein structure network modeling are combined to dissect molecular mechanisms of Hsp90 regulation by the client recruiter cochaperones. Dynamic signatures of the Hsp90-cochaperone complexes are manifested in differential modulation of the conformational mobility in the Hsp90 lid motif. Consistent with the experiments, …