Biochemistry, Biophysics, and Structural Biology Commons^™

Cellular And Molecular Targets Of Menthol Actions, Murat Oz, Eslam El Nebrisi, Keun-Hang Susan Yang, Frank Christopher Howarth, Lina T. Al Kury

Mathematics, Physics, and Computer Science Faculty Articles and Research

Menthol belongs to monoterpene class of a structurally diverse group of phytochemicals found in plant-derived essential oils. Menthol is widely used in pharmaceuticals, confectionary, oral hygiene products, pesticides, cosmetics, and as a flavoring agent. In addition, menthol is known to have antioxidant, anti-inflammatory, and analgesic effects. Recently, there has been renewed awareness in comprehending the biological and pharmacological effects of menthol. TRP channels have been demonstrated to mediate the cooling actions ofmenthol. There has been new evidence demonstrating thatmenthol can significantly influence the functional characteristics of a number of different kinds of ligand and voltage-gated ion channels, indicating that at …

Testing The Independence Hypothesis Of Accepted Mutations For Pairs Of Adjacent Amino Acids In Protein Sequences, Jyotsna Ramanan, Peter Revesz

School of Computing: Faculty Publications

Evolutionary studies usually assume that the genetic mutations are independent of each other. However, that does not imply that the observed mutations are independent of each other because it is possible that when a nucleotide is mutated, then it may be biologically beneficial if an adjacent nucleotide mutates too. With a number of decoded genes currently available in various genome libraries and online databases, it is now possible to have a large-scale computer-based study to test whether the independence assumption holds for pairs of adjacent amino acids. Hence the independence question also arises for pairs of adjacent amino acids within …

Physiological Evidence For Isopotential Tunneling In The Electron Transport Chain Of Methane-Producing Archaea, Nikolas Duszenko, Nicole R. Buan

Department of Biochemistry: Faculty Publications

Many, but not all, organisms use quinones to conserve energy in their electron transport chains. Fermentative bacteria and methane-producing archaea (methanogens) do not produce quinones but have devised other ways to generate ATP. Methanophenazine (MPh) is a unique membrane electron carrier found in Methanosarcina species that plays the same role as quinones in the electron transport chain. To extend the analogy between quinones and MPh, we compared the MPh pool sizes between two well-studied Methanosarcina species, Methanosarcina acetivorans C2A and Methanosarcina barkeri Fusaro, to the quinone pool size in the bacterium Escherichia coli. We found the quantity of MPh per …

Chloroformate Derivatization For Tracing The Fate Of Amino Acids In Cells And Tissues By Multiple Stable Isotope Resolved Metabolomics (Msirm), Ye Yang, Teresa W. -M. Fan, Andrew N. Lane, Richard M. Higashi

Center for Environmental and Systems Biochemistry Faculty Publications

Amino acids have crucial roles in central metabolism, both anabolic and catabolic. To elucidate these roles, steady-state concentrations of amino acids alone are insufficient, as each amino acid participates in multiple pathways and functions in a complex network, which can also be compartmentalized. Stable Isotope-Resolved Metabolomics (SIRM) is an approach that uses atom-resolved tracking of metabolites through biochemical transformations in cells, tissues, or whole organisms. Using different elemental stable isotopes to label multiple metabolite precursors makes it possible to resolve simultaneously the utilization of these precursors in a single experiment. Conversely, a single precursor labeled with two (or more) different …

A Programmable Optical Stimulator For The Drosophila Eye, Xinping Chen, Walter D. Leon-Salas, Taylor Zigon, Donald F. Ready, Vikki M. Weake

Department of Biochemistry Faculty Publications

A programmable optical stimulator for Drosophila eyes is presented. The target application of the stimulator is to induce retinal degeneration in fly photoreceptor cells by exposing them to light in a controlled manner. The goal of this work is to obtain a reproducible system for studying age-related changes in susceptibility to environmental ocular stress. The stimulator uses light emitting diodes and an embedded computer to control illuminance, color (blue or red) and duration in two independent chambers. Further, the stimulator is equipped with per-chamber light and temperature sensors and a fan to monitor light intensity and to control temperature. An …

Modeling Of Dynamic Allostery In Proteins Enabled By Machine Learning, Mohsen Botlani-Esfahani

USF Tampa Graduate Theses and Dissertations

Regulation of protein activity is essential for normal cell functionality. Many proteins are regulated allosterically, that is, with spatial gaps between stimulation and active sites. Biological stimuli that regulate proteins allosterically include, for example, ions and small molecules, post-translational modifications, and intensive state-variables like temperature and pH. These effectors can not only switch activities on-and-off, but also fine-tune activities. Understanding the underpinnings of allostery, that is, how signals are propagated between distant sites, and how transmitted signals manifest themselves into regulation of protein activity, has been one of the central foci of biology for over 50 years. Today, the importance …

Quaternary Interactions And Supercoiling Modulate The Cooperative Dna Binding Of Agt, Manana Melikishvili, Michael G. Fried

Center for Structural Biology Faculty Publications

Human O⁶-alkylguanine-DNA alkyltransferase (AGT) repairs mutagenic O⁶-alkylguanine and O⁴-alkylthymine adducts in single-stranded and duplex DNAs. The search for these lesions, through a vast excess of competing, unmodified genomic DNA, is a mechanistic challenge that may limit the repair rate in vivo. Here, we examine influences of DNA secondary structure and twist on protein–protein interactions in cooperative AGT complexes formed on lesion-free DNAs that model the unmodified parts of the genome. We used a new approach to resolve nearest neighbor (nn) and long-range (lr) components from the ensemble-average cooperativity, ω_ave. We found …

Regulation Of Extracellular Signal-Regulated Kinase By Histone Deacetylase 6, Jheng-Yu Wu

USF Tampa Graduate Theses and Dissertations

Extracellular signal-regulated kinases 1/2 (ERK1/2) are important kinases regulating cell proliferation and cell migration, and have been established as therapeutic targets for cancer treatment. Previously, we found that ERK1 phosphorylates histone deacetylase 6 (HDAC6) to regulate its enzymatic activity. However, whether HDAC6 reciprocally modulates ERK1 activity is unknown. Here, we have discovered that ERK1/2 are acetylated proteins and shown that HDAC6 manipulates ERK1’s kinase activity via deacetylation. We demonstrated that both ERK1 and ERK2 interact with HDAC6 physically. We showed that the acetylation level of GST-ERK1/2 increased in a dose- and time-dependent manner upon treatment with a pan-HDAC inhibitor, Trichostatin …

Rational Drug Design Directed At Blocking The Initial Signaling Events In Lipopolysaccharide-Induced Sepsis., Christopher A. Tipton

Theses

Systemic Inflammatory Response Syndrome (SIRS) is classified as an immune system response to an infectious state. If left untreated, SIRS leads to sepsis, septic shock, end-organ dysfunction, and death. As a patient progresses through these stages, associations of acute respiratory distress, disseminated intravascular coagulation, and acute renal failure persist, resulting in millions of deaths annually. Lipopolysaccharide (LPS), a bacterial endotoxin, is released into the blood stream, triggering SIRS. LPS is found in the outer cell-wall of Gram-negative bacteria and is responsible for initiation of a devastating cytokine storm. One of the regions of LPS, lipid A, is a polyacylated glucosamine …

Mechanism-Informed Refinement Reveals Altered Substrate-Binding Mode For Catalytically Competent Nitroreductase, Warintra Pitsawong, Chad A. Haynes, Ronald L. Koder, David W. Rodgers, Anne-Frances Miller

Chemistry Faculty Publications

Nitroreductase from Enterobacter cloacae (NR) reduces diverse nitroaromatics including herbicides, explosives and prodrugs, and holds promise for bioremediation, prodrug activation and enzyme-assisted synthesis. We solved crystal structures of NR complexes with bound substrate or analog for each of its two half-reactions. We complemented these with kinetic isotope effect (KIE) measurements elucidating H-transfer steps essential to each half-reaction. KIEs indicate hydride transfer from NADH to the flavin consistent with our structure of NR with the NADH analog nicotinic acid adenine dinucleotide (NAAD). The KIE on reduction of p-nitrobenzoic acid (p-NBA) also indicates hydride transfer, and requires revision of …

Discovering Antibacterial And Anti-Resistance Agents Targeting Multi-Drug Resistant Eskape Pathogens, Renee Fleeman

USF Tampa Graduate Theses and Dissertations

Antibiotic resistance has been a developing problem for mankind in recent decades and multi-drug resistant bacteria are now encountered that are resistant to all treatment options available. In 2014, the World Health Organization announced that this problem is driving us towards a “post-antibiotic era” that will change the face of modern medicine as we know it. If lack of novel antibiotic development and FDA approval continues, by the year 2050, 10 million people will die each year to an antimicrobial resistant bacterial infection. With lack of pharmaceutical industry involvement in developing novel antibiotics, the responsibility now lies within the academic …

Hydrogenation Of Organic Matter As A Terminal Electron Sink Sustains High Co2:Ch4 Production Ratios During Anaerobic Decomposition, Rachel M. Wilson, Malak M. Tfaily, Virginia I. Rich, Jason K. Keller, Scott D. Bridgham, Cassandra Medvedeff Zalman, Laura Meredith, Paul J. Hanson, Mark Hines, Laurel Pfeifer-Meister, Scott R. Saleska, Patrick Crill, William T. Cooper, Jeff P. Chanton, Joel E. Kostka

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Once inorganic electron acceptors are depleted, organic matter in anoxic environments decomposes by hydrolysis, fermentation, and methanogenesis, requiring syntrophic interactions between microorganisms to achieve energetic favorability. In this classic anaerobic food chain, methanogenesis represents the terminal electron accepting (TEA) process, ultimately producing equimolar CO₂ and CH₄ for each molecule of organic matter degraded. However, CO₂:CH₄ production in Sphagnum-derived, mineral-poor, cellulosic peat often substantially exceeds this 1:1 ratio, even in the absence of measureable inorganic TEAs. Since the oxidation state of C in both cellulose-derived organic matter and acetate is 0, and CO₂ has …

Structure And Activity Of Metallo-Peptides, Christian C. Tang

USF Tampa Graduate Theses and Dissertations

Metal ions are ubiquitously found in all living systems and play vital roles in supporting life forms by performing an array of biological activities. Such biological activities include binding and transforming organic molecules, and also acting as active centers and cofactors for catalysis of various acid-base and redox reactions in biological system. The main focus in bioinorganic chemistry is to elucidate the structural and functional roles of metals in biological systems. Among all transition metal ions, Cu²⁺ and Fe³⁺ are especially versatile and important due to their abilities to go through redox efficiently.

This dissertation can be divided …

Transcriptomic Differentiation Underlying Marine‐To‐Freshwater Transitions In The South American Silversides Odontesthes Argentinensis And O. Bonariensis (Atheriniformes), Lily Hughes, Gustavo Somoza, Bryan Nguyen, James Bernot, Mariano Gonzalez-Castro, Juan Martin Diaz De Astarloa, Guillermo Orti

Computational Biology Institute

Salinity gradients are critical habitat determinants for freshwater organisms. Silverside fishes in the genus Odontesthes have recently and repeatedly transitioned from marine to freshwater habitats, overcoming a strong ecological barrier. Genomic and transcriptomic changes involved in this kind of transition are only known for a few model species. We present new data and analyses of gene expression and microbiome composition in the gills of two closely related silverside species, marine O. argentinensis and freshwater O. bonariensis and find more than three thousand transcripts differentially expressed, with osmoregulatory/ion transport genes and immune genes showing very different expression patterns across species. Interspecific …

Mutations In The Transmembrane Domain And Cytoplasmic Tail Of Hendra Virus Fusion Protein Disrupt Virus-Like-Particle Assembly, Nicolás P. Cifuentes-Muñoz, Weina Sun, Greeshma Ray, Phuong Tieu Schmitt, Stacy Webb, Kathleen Gibson, Rebecca Ellis Dutch, Anthony P. Schmitt

Molecular and Cellular Biochemistry Faculty Publications

Hendra virus (HeV) is a zoonotic paramyxovirus that causes deadly illness in horses and humans. An intriguing feature of HeV is the utilization of endosomal protease for activation of the viral fusion protein (F). Here we investigated how endosomal F trafficking affects HeV assembly. We found that the HeV matrix (M) and F proteins each induced particle release when they were expressed alone but that their coexpression led to coordinated assembly of virus-like particles (VLPs) that were morphologically and physically distinct from M-only or F-only VLPs. Mutations to the F protein transmembrane domain or cytoplasmic tail that disrupted endocytic trafficking …

Cross Reactivity Of Immune Responses To Porcine Reproductive And Respiratory Syndrome Virus Infection, Ignacio Correas, Fernando A. Osorio, David Steffen, Asit K. Pattnaik, Hiep L. X. Vu

School of Veterinary and Biomedical Sciences: Faculty Publications

Because porcine reproductive and respiratory syndrome virus (PRRSV) exhibits extensive genetic variation among field isolates, characterizing the extent of cross reactivity of immune responses, and most importantly cell-mediated immunity (CMI), could help in the development of broadly cross-protective vaccines. We infected 12 PRRSV-naïve pigs with PRRSV strain FL12 and determined the number of interferon (IFN)-γ secreting cells (SC) by ELISpot assay using ten type 2 and one type 1 PRRSV isolates as recall antigens. The number of IFN-γ SC was extremely variable among animals, and with exceptions, late to appear. Cross reactivity of IFN-γ SC among type 2 isolates was …

Crystal Structure Of Yersinia Pestis Virulence Factor Yfea Reveals Two Polyspecific Metal-Binding Sites, Christopher D. Radka, Lawrence J. Delucas, Landon S. Wilson, Matthew B. Lawrenz, Robert D. Perry, Stephen G. Aller

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Gram-negative bacteria use siderophores, outer membrane receptors, inner membrane transporters and substrate-binding proteins (SBPs) to transport transition metals through the periplasm. The SBPs share a similar protein fold that has undergone significant structural evolution to communicate with a variety of differentially regulated transporters in the cell. In Yersinia pestis, the causative agent of plague, YfeA (YPO2439, y1897), an SBP, is important for full virulence during mammalian infection. To better understand the role of YfeA in infection, crystal structures were determined under several environmental conditions with respect to transition-metal levels. Energy-dispersive X-ray spectroscopy and anomalous X-ray scattering data show that …

The Chondrocyte Channelome: A Novel Ion Channel Candidate In The Pathogenesis Of Pectus Deformities, Anthony J. Asmar

Biological Sciences Theses & Dissertations

Costal cartilage is a type of rod-like hyaline cartilage connecting the ribs to the sternum. The chest wall deformities pectus excavatum (PE) and pectus carinatum (PC) involve displacement of the sternum causing a depression or protrusion of the chest. There is little knowledge about costal cartilage and pectus deformities with much of its understanding based on assumptions from articular cartilage. Chondrocytes are subjected to a constantly changing environment with fluctuations in pH and osmolarity. Ion channels detect these changes and in turn regulate proliferation, differentiation, and extracellular matrix production. Using ion channel qPCR arrays, we produced expression profiles for normal, …

Biochemistry, Chavonda Mills, Shaundra Walker

Chemistry Grants Collections

This Grants Collection for Biochemistry was created under a Round Five ALG Textbook Transformation Grant.

Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.

Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials:

• Linked Syllabus
• Initial Proposal
• Final Report

Biochemistry Lecture Notes, Chavonda Mills, Shaundra Walker

Chemistry Ancillary Materials

The following set of lecture notes are ancillary materials for Oregon State University's Biochemistry: Free for All.

This ancillary set was created under a Round Five ALG Textbook Transformation Grant. They are also available in an open-course format through LibGuides:

http://libguides.gcsu.edu/millsbiochem3510

Generating Enzyme And Radical‐Mediated Bisubstrates As Tools For Investigating Gcn5‐Related N‐Acetyltransferases, Cory T. Reidl, Karolina A. Majorek, Joseph Dang, David Tran, Kristen Jew, Melissa Law, Yasmine Payne, Wladek Minor, Daniel P. Becker, Misty L. Kuhn

Chemistry: Faculty Publications and Other Works

Gcn5‐related N‐acetyltransferases (GNATs) are found in all kingdoms of life and catalyze important acyl transfer reactions in diverse cellular processes. While many 3D structures of GNATs have been determined, most do not contain acceptor substrates in their active sites. To expand upon existing crystallographic strategies for improving acceptor‐bound GNAT structures, we synthesized peptide substrate analogs and reacted them with CoA in PA4794 protein crystals. We found two separate mechanisms for bisubstrate formation: (a) a novel X‐ray induced radical‐mediated alkylation of CoA with an alkene peptide and (b) direct alkylation of CoA with a halogenated peptide. Our approach is widely …

Perspective: The Physics, Diagnostics, And Applications Of Atmospheric Pressure Low Temperature Plasma Sources Used In Plasma Medicine, M. Laroussi

Electrical & Computer Engineering Faculty Publications

Low temperature plasmas have been used in various plasma processing applications for several decades. But it is only in the last thirty years or so that sources generating such plasmas at atmospheric pressure in reliable and stable ways have become more prevalent. First, in the late 1980s, the dielectric barrier discharge was used to generate relatively large volume diffuse plasmas at atmospheric pressure. Then, in the early 2000s, plasma jets that can launch cold plasma plumes in ambient air were developed. Extensive experimental and modeling work was carried out on both methods and much of the physics governing such sources …

An Approach To Identify Mycobacteriophage Diversity Prior To Dna Sequencing, Charles Gregory

Mahurin Honors College Capstone Experience/Thesis Projects

Over 6,869 Mycobacteriophages have been isolated and purified. Of these, 1,367 genomes have been sequenced at the DNA level and more are added each year through the SEA-PHAGES program. Sequenced mycobacteriophages are grouped into clusters based on a 50% or greater nucleotide identity. The number and breadth of these clusters represents the diversity present in the environment. Each year, as new phages are discovered by students in the SEA-PHAGES program, the question arises, “Which isolates should we sequence?” In order to sequence phages that represent the greatest possible diversity, and thus broaden under-represented clusters and identify new singletons, we need …

Investigating The Synergistic Effects Of Cisplatin And Two Curcuminoid Compounds On Cancer, Denis Hodzic

Mahurin Honors College Capstone Experience/Thesis Projects

Cisplatin is an anti-cancer drug effective against several cancers which can produce the serious side-effect of hearing loss. Curcumin, a natural plant compound, can increase the activity of cisplatin against cancer and counteract cisplatin’s effect against hearing. Because curcumin exhibits poor bioavailability, there is considerable interest in developing synthetic curcumin analogs (curcuminoids) that are more soluble and which retain anti-cancer activity and otoprotective function. This study investigated whether two curcuminoids, EF-24 and CLEFMA, increase the cytotoxic and ototoxic effects of cisplatin against the lung cancer cell line, A549, and the colorectal cancer cell line, Caco2. Cytotoxicity was measured by using …

The General Amino Acid Permease Gap1 Is Regulated Differentially By Torc1 Activation And Inhibition, Ray Bowman

D.U.Quark

How does cell signaling in response to extracellular stressors impact the trafficking of membrane proteins? In particular, the TORC1 complex plays a key role in this process and while some details of this system have reported, in a recent Journal of Biological Chemistry publication, Andre’s group has revealed new details of this pathway focusing on the general amino acid permease Gap1 as a model cargo. Andre et al. describe a novel and distinct pathway wherein ubiquitylation and downregulation of Gap1 is regulated not only by amino acid-induced activation of TORC1, but also by numerous sources of TORC1 inhibition and cellular …

Spatiotemporal Regulation Of Atg1 Kinase Activation In Selective Autophagy, Ning Sun

D.U.Quark

Autophagy is a potent intracellular degradation system and thus its activation requires exquisite regulation to maintain cellular homeostasis. Atg1, a serine-threonine protein kinase, is essential in both selective and non-selective autophagy. New findings suggest that in selective autophagy, Atg1 is activated at the vacuole by convergence of two independent recruitment pathways to prevent aberrant autophagy induction.

Hsp70 Conformational Plasticity Allows For Expansive Chaperone Role, Megan Bean

D.U.Quark

The Hsp70 system is an essential component of chaperone activity in many organisms. Hsp70 functions include: protein folding, aggregation prevention, trafficking, and enzyme regulation. Hsp70’s ability to bind such a vast array of substrates suggests wide range of conformational plasticity. By utilizing a single mode optical tweezers technique, Mashaghi1 et al., confirms previous theories Hsp70 binds and stabilizes extended peptide segments but also partially folded and near-native protein.

Plasmodium Falciparum 26s Proteasome Network: A Mystery Solved, Christina Grogan

D.U.Quark

One ofthe most devastating diseases thatthreatens the world population is malaria. The 26S proteasome complex of the malaria parasite Plasmodium falciparum, which was previously unknown, was characterized by the authors through an affinity purification protocol that isolated functional 26S proteasome complexes. This allowed for the identification of subunit composition and PfUSP14, a proteasomeassociated deubiquitinase. This new understanding presents a potential target to disrupt protein regulation in thequest for effective antimalarial strategies.

Autophagy Inhibition In Pain: Role Of A Microrna, Andrea Stevens

D.U.Quark

Neuropathic pain caused by peripheral nerve injury (PNI) leads to the activation and infiltration of microglial cells and to a neuroinflammatory-induced pain state. miRNAs and autophagy are two main factors and/or mechanisms which have the ability to alter the pain state. In this study, miR-195 was shown to be markedly increased after PNI and associated with the pain phenotype. In addition, inhibition of autophagy in vivo led to p62 accumulation, decreased production of LC3, and inhibition of ATG14.

Electronic Structure And Quassiclassical Dynamics Of [2+2] Tetrafluoroethylene Cycloaddition Reactions, Steven Jones, Daniel Ess

Journal of Undergraduate Research

Cycloaddition reactions are key reactions used to construct complex cyclic scaffolds (large networks of carbon atoms that can be used in catalysis, synthesis, etc.). While classical reactions that form 6-membered rings are well-known and generally have a one-step reaction mechanism, 4-member ring-forming reactions are much less used, but could be very valuable for the construction of cyclobutane structures.

Tetrafluoroethylene (TFE) is used on a large scale by Dow and other chemical companies to form hydrofluoro compounds such as teflon. The current understanding of the mechanism of cycloaddition reactions with TFE is limited. Standard hydrocarbon reactions proceed via a welldocumented, concerted …