Biochemistry Commons^™

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 …

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 …

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

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 …

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.

Inhibiting Translesion Dna Synthesis As An Approach To Combat Drug Resistance To Dna Damaging Agents, Jung-Suk Choi, Seol Kim, Edward Motea, Anthony J. Berdis

Chemistry Faculty Publications

Anti-cancer agents exert therapeutic effects by damaging DNA. Unfortunately, DNA polymerases can effectively replicate the formed DNA lesions to cause drug resistance and create more aggressive cancers. To understand this process at the cellular level, we developed an artificial nucleoside that visualizes the replication of damaged DNA to identify cells that acquire drug resistance through this mechanism. Visualization is achieved using "click" chemistry to covalently attach azide-containing fluorophores to the ethynyl group present on the nucleoside analog after its incorporation opposite damaged DNA. Flow cytometry and microscopy techniques demonstrate that the extent of nucleotide incorporation into genomic DNA is enhanced …

Interleukin-18 Polymorphism As An Inflammatory Index In Metabolic Syndrome: A Preliminary Study, Syeda Sadia Fatima, Zehra Jamil, Syed Hani Abidi, Daniyal Nadeem, Zara Bashir, Ahmed Ansari

Department of Biological & Biomedical Sciences

Aim: To assess circulatory levels of interleukin-18 (IL-18) and determine whether the presence of IL-18 promoter polymorphism influences metabolic syndrome phenotypes.
Methods: This study recruited one hundred and eighty individuals divided into three groups with sixty subjects each as: Normal weight (18.0-22.9 kg/m2), overweight (23.0-25.9 kg/m2) and obese (> 26.0 kg/m2) according to South Asian criteria of BMI. Fasting blood glucose (FBG), Lipid profile, insulin, IL-18 and tumor necrosis factor (TNF)alpha were measured using ELISA kits, whereas low density lipoprotein (LDL)-cholesterol, insulin resistance (HOMA-IR) and insulin sensitivity (QUICKI) were calculated. The body fat percentage (BF) was measured through bioelectrical impedance …

Exploring Cancer Metabolism Using Stable Isotope-Resolved Metabolomics (Sirm), Ronald C. Bruntz, Andrew N. Lane, Richard M. Higashi, Teresa W. -M. Fan

Center for Environmental and Systems Biochemistry Faculty Publications

Metabolic reprogramming is a hallmark of cancer. The changes in metabolism are adaptive to permit proliferation, survival, and eventually metastasis in a harsh environment. Stable isotope-resolved metabolomics (SIRM) is an approach that uses advanced approaches of NMR and mass spectrometry to analyze the fate of individual atoms from stable isotope-enriched precursors to products to deduce metabolic pathways and networks. The approach can be applied to a wide range of biological systems, including human subjects. This review focuses on the applications of SIRM to cancer metabolism and its use in understanding drug actions.

Growth Trade-Offs Accompany The Emergence Of Glycolytic Metabolism In Shewanella Oneidensis Mr-1, Lon Chubiz, Christopher Marx

Biology Department Faculty Works

Bacteria increase their metabolic capacity via the acquisition of genetic material or by the mutation of genes already present in the genome. Here, we explore the mechanisms and trade-offs involved when Shewanella oneidensis, a bacterium that typically consumes small organic and amino acids, rapidly evolves to expand its metabolic capacity to catabolize glucose after a short period of adaptation to a glucose-rich environment. Using whole-genome sequencing and genetic approaches, we discovered that deletions in a region including the transcriptional repressor (nagR) that regulates the expression of genes associated with catabolism of N-acetylglucosamine are the common basis for evolved glucose metabolism …

Current Status Of Helicobacter Pylori Association With Haematological And Cardiovascular Diseases: A Mini Review, Jibran Sualeh Muhammad, Syed Faisal Zaidi, Sheikh Abdul Saeed, Muhammad Ishaq

Department of Biological & Biomedical Sciences

Helicobacter pylori infection is considered the most commonly prevalent gastrointestinal pathogen where it manages to survive despite the hostile environment of human stomach, leading to various gastric diseases including gastric cancer. Due to the chronic inflammatory state induced by H. pylori and its interaction with host immune system have diverted researchers to investigate its correlation with systemic diseases outside of the gastrointestinal tract. This literature review was done to explore the association of H. pylori infection with haematological and cardiovascular diseases. We used medical subject heading (MeSH) terms "Helicobacter pylori" with "inflammation," "haematological diseases," "coronary heart diseases" or "vascular diseases" …

The Mechanistic Requirements Of Passive H+ Import Through The Na, K-Atpase, Kevin S. Stanley

Theses and Dissertations

This work focuses on the elucidation of the mechanism of passive proton import through the Na,K-ATPase. This enzyme uses the energy in ATP hydrolysis to exchange three intracellular Na+ for two extracellular K+ to maintain ion gradients within the cell, and while in the absence of physiological external Na+ and K+, the phosphorylated externally open (E2P) conformation passively imports protons, generating an inward current (IH). Chapter one reports on the effects of intracellular cations and nucleotides to shift the Na,K-ATPase into the E2P conformation. We identified that a combination of either internal Na+ and ATP or K+ and Pi. In …

A Novel Population Of Cardiovascular Progenitors Persist In Neonates As Mesendodermal Cells, Julia Kim

Loma Linda University Electronic Theses, Dissertations & Projects

The rise in mortality due to cardiovascular disease has increased the need to develop an efficient regenerative therapeutic for heart failure. Numerous cell-based therapies have been investigated for myocardial regeneration; however, an optimal progenitor has yet to be discovered. Identifying a resident cell population with enhanced ability to differentiate into multiple lineages would greatly contribute to the field of stem cell-based regenerative therapy. Evidence suggests that endogenous cardiovascular progenitor cells (CPCs) that have been isolated from the heart itself express ISL1, KDR, and MESP1, and are capable of differentiating into all major cardiac lineages. The earlier developmental stage at which …