Open Access. Powered by Scholars. Published by Universities.®

Biochemistry Commons

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 1861 - 1890 of 6985

Full-Text Articles in Biochemistry

Self-Assembled Thermoresponsive Nanogel From Grafted Hyaluronic Acid As A Biocompatible Delivery Platform For Curcumin With Enhanced Drug Loading And Biological Activities, Jittima Amie Luckanagul, Pahweenvaj Ratnatilaka Na Bhuket, Chawanphat Muangnoi, Pranee Rojsitthisak, Qian Wang, Pornchai Rojsitthisak Jan 2021

Self-Assembled Thermoresponsive Nanogel From Grafted Hyaluronic Acid As A Biocompatible Delivery Platform For Curcumin With Enhanced Drug Loading And Biological Activities, Jittima Amie Luckanagul, Pahweenvaj Ratnatilaka Na Bhuket, Chawanphat Muangnoi, Pranee Rojsitthisak, Qian Wang, Pornchai Rojsitthisak

Faculty Publications

A hyaluronic acid-grafted poly(N-isopropylacrylamide) (HA-pNIPAM) was synthesized as a polymeric nanogel platform for encapsulation and delivery of hydrophobic bioactive compounds using curcumin as a model drug. As demonstrated by transmission electron microscopy and dynamic light scattering techniques, the HA-pNIPAM was simply assembled into spherical nano-sized particles with the thermoresponsive behavior. The success of curcumin aqueous solubilization was confirmed by fluorescent spectroscopy. The resulting nanogel formulation enhanced the aqueous solubility and uptake into NIH-3T3 cells of curcumin. This nanogel formulation also demonstrates cytocompatibility against NIH-3T3 cells, which deems it safe as a delivery vehicle. Moreover, the formulation has a slight skin-protection …


Potential Counter Regulatory Effects Of A Gut Microbiota Metabolite In Alleviating Down-Regulation Krüppel-Like Factor 4 In Intestinal Inflammation, Ylva Forslund Jan 2021

Potential Counter Regulatory Effects Of A Gut Microbiota Metabolite In Alleviating Down-Regulation Krüppel-Like Factor 4 In Intestinal Inflammation, Ylva Forslund

Theses, Dissertations and Capstones

Inflammatory bowel disease (IBD) is a medical condition characterized by chronic inflammation of the intestinal epithelium. Krüppel-like factor 4 (KLF4), a zinc finger transcription factor, is vital for maintaining intestinal epithelial homeostasis. KLF4 promotes differentiation of goblet cells that generate the protective mucus layer. Reduced goblet cell number and defective mucus layer are associated with IBD. Shortchain fatty acids (SCFA) are known to play an important role in the maintenance of a strong and healthy intestinal epithelial layer and also in goblet cell differentiation. However, whether the positive effects of SCFAs on goblet cells are mediated, at least partly, via …


Root Nrt, Nir, Amt, Gs, Gogat And Gdh Expression Levels Reveal No Andaba Mediated Drought Tolerance In Brassica Juncea L., Seema Sahay, Luis Robledo-Arratia, Katarzyna Glowacka, Meetu Gupta Jan 2021

Root Nrt, Nir, Amt, Gs, Gogat And Gdh Expression Levels Reveal No Andaba Mediated Drought Tolerance In Brassica Juncea L., Seema Sahay, Luis Robledo-Arratia, Katarzyna Glowacka, Meetu Gupta

Department of Biochemistry: Faculty Publications

Little is known about the interactive effects of exogenous nitric oxide (NO) and abscisic acid (ABA) on nitrogen (N) metabolism and related changes at molecular and biochemical levels under drought stress. The present study highlights the independent and combined effect of NO and ABA (grouped as “nitrate agonists”) on expression profiles of representative key genes known to be involved in N-uptake and assimilation, together with proline metabolism, N–NO metabolism enzyme’s activity and nutrient content in polyethylene glycol (PEG) treated roots of Indian mustard (B. juncea cv. Varuna). Here we report that PEG mediated drought stress negatively inhibited growth performance, as …


Validation Of A Deployable Proteomic Assay For The Serological Screening Of Sexual Assault Samples, Catherine O'Sullivan Brown Jan 2021

Validation Of A Deployable Proteomic Assay For The Serological Screening Of Sexual Assault Samples, Catherine O'Sullivan Brown

Electronic Theses and Dissertations

Protein mass spectrometry (MS) has emerged as a technique to supplant traditional serological tests for body fluid identification. It was hypothesized that proteomic techniques would surpass the sensitivity and specificity of traditional serological techniques. An automated workflow coupled with protein MS has been developed for the confirmatory identification of five biological fluids. A developmental validation was completed, assessing parameters such as reproducibility, sensitivity, ion suppression, and limit of detection. Implementation was determined through tandem sample processing by MS, traditional serological tests, and standard DNA profiling methods. The MS approach offered superior detection limits while also providing true confirmatory results, producing …


Nucleic Acids Promote Oligomerization Of Immunoglobulin G, Alexa Gomez Jan 2021

Nucleic Acids Promote Oligomerization Of Immunoglobulin G, Alexa Gomez

Electronic Theses and Dissertations

Nucleic acids have been found to prevent aggregation as chaperones, as well as act as co-factors and promote aggregation of amyloidogenic proteins leading to various diseases. Immunoglobulin G, IgG, are prone to aggregate as therapeutic proteins, and light chains of IgG can form amyloid fibrils, causing a disease known as light chain amyloidosis. Here we discuss the effect nucleic acids have on full-length immunoglobulin G aggregation. Our results show G-quadruplex DNA, and bulk DNA lead to oligomerization of full-length IgG, and induce increases in secondary structure. Tryptophan fluorescence indicates structural changes are occurring in the presence of DNA. Additionally, IgG …


Bcs1l Interactors And Rieske Docking, Ashley Meyer, Emma Pastoor, Amy Wilstermann, Rachael Baker Jan 2021

Bcs1l Interactors And Rieske Docking, Ashley Meyer, Emma Pastoor, Amy Wilstermann, Rachael Baker

Summer Research

BCS1L interacts with many differentially localized proteins with functions ranging from metabolism to involvement in complex disease pathways


The Effects Of Rolipram, A Selective Phosphodiesterase Inhibitor, On Immortalized Schwann Cell Proliferation, Akap95 And Cyclin D3 Expression, Kyle P. Kenney, Mary Pistack, Angela Asirvatham Jan 2021

The Effects Of Rolipram, A Selective Phosphodiesterase Inhibitor, On Immortalized Schwann Cell Proliferation, Akap95 And Cyclin D3 Expression, Kyle P. Kenney, Mary Pistack, Angela Asirvatham

Student Research Poster Presentations 2021

Schwann cells are a vital component of the Peripheral Nervous System and aid in the repair of axons following injury. The regulation of Schwann cell growth in vitro is facilitated by heregulin, a neuron-secreted growth factor, and an unknown mitogen that activates the cyclic adenosine monophosphate (cAMP) pathway. The abundance of intracellular cAMP is regulated by a family of enzymes called phosphodiesterases (PDEs). PDE inhibitors such as rolipram have therapeutic potential in various disorders and function by increasing the levels of intracellular cAMP. A-Kinase anchoring proteins (AKAPs), a family of scaffolding proteins that belong to the cAMP/Protein Kinase A (PKA) …


Green Team - Ecological Restoration Of Plaster Creek, Jia Luchs, Caleb Mathai, Rachel Warners, David Warners, Deanna Geelhoed Jan 2021

Green Team - Ecological Restoration Of Plaster Creek, Jia Luchs, Caleb Mathai, Rachel Warners, David Warners, Deanna Geelhoed

Student Papers and Reports

Plaster Creek, though its watershed is home to many potential stewards in Grand Rapids, is the most polluted creek in West Michigan. The Green Team, a branch of Plaster Creek Stewards, is a group of students that work during the summer with a focus on research, education, and working directly to restore Plaster Creek. The team works toward this goal through urban green infrastructure, utilizing native plants to manage stormwater. Two Calvin students, Caleb Mathai and Jia Luchs, one high school intern, Ben Zwart, and twelve high school students living in the Plaster Creek watershed were hired by PCS this …


Synthetic Pathways For Potential Platinum 1,10-Phenanthroline Compounds, Jacob Young Jan 2021

Synthetic Pathways For Potential Platinum 1,10-Phenanthroline Compounds, Jacob Young

Mahurin Honors College Capstone Experience/Thesis Projects

There are extremely important uses for platinum when it comes to the treatment of cancers and dementias. One potential therapeutic combines platinum with a structure known as phenanthroline. This platinum phenanthroline structure is normally extremely water-insoluble, rendering it difficult to study and use in biological systems. The Williams’ Biochemistry Laboratory endeavored to find a simpler synthetic pathway for a water-soluble phenanthroline product. While unsuccessful in identifying a product as of yet, many synthetic pathways have been ruled out, and more hypothetical pathways are being formulated for testing.

Among the strategies analyzed are varying solvent, reagents, apparatus, methodology, and temperature in …


Analyzing Single Ion Channel Activity In A Lipid Bilayer, David Ruiter, Loren Haarsma Jan 2021

Analyzing Single Ion Channel Activity In A Lipid Bilayer, David Ruiter, Loren Haarsma

Summer Research

Bilayers of lipid molecules form the basis of the cell membranes in living organisms. An ion channel is a type of molecule that can temporarily open a channel in a lipid bilayer in order to allow specific ions in and out. Problems with ion channels and their interactions with lipid bilayers are associated with several diseases, including osteoporosis. Carefully controlling the type of lipid in the bilayer, and its temperature, gives us tools to study the basic biophysics of these systems


Effects Of Resin Chemistries On The Selective Removal Of Industrially Relevant Metal Ions Using Wafer-Enhanced Electrodeionization, Humeyra B. Ulusoy Erol, Christa N. Hestekin, Jamie A. Hestekin Jan 2021

Effects Of Resin Chemistries On The Selective Removal Of Industrially Relevant Metal Ions Using Wafer-Enhanced Electrodeionization, Humeyra B. Ulusoy Erol, Christa N. Hestekin, Jamie A. Hestekin

Chemical Engineering Faculty Publications and Presentations

Wafer-enhanced electrodeionization (WE-EDI) is an electrically driven separations technology that occurs under the influence of an applied electric field and heavily depends on ion exchange resin chemistry. Unlike filtration processes, WE-EDI can be used to selectively remove ions even from high concentration systems. Because every excess ion transported increases the operating costs, the selective separation offered by WE-EDI can provide a more energy-efficient and cost-effective process, especially for highly concentrated salt solutions. This work reports the performance comparison of four commonly used cation exchange resins (Amberlite IR120 Na+, Amberlite IRP 69, Dowex MAC 3 H+, and …


Development Of A Dna Biosensor Using Crispr/Dcas9 On A Graphene Oxide Surface For Detecting Antibiotic Resistance Genes, Wendy Cecil Jan 2021

Development Of A Dna Biosensor Using Crispr/Dcas9 On A Graphene Oxide Surface For Detecting Antibiotic Resistance Genes, Wendy Cecil

Mahurin Honors College Capstone Experience/Thesis Projects

Antibiotic resistance is a rapidly spreading global threat to human health. Previously in our lab, we developed a simple method for facile detection of antibiotic resistance genes (ARGs) in bacteria. This DNA detection system takes advantage of the CRISPR-Cas system (Clustered Regularly Interspaced Short Palindromic Repeat and CRISPRAssociated Protein). We designed CRISPR in complex with nuclease deactivated Cas9 (dCas9) on graphene oxide (GO) sheets conjugated with Cas9 antibodies. Single guide RNA (sgRNA) was customized to program dCas9 for target DNA binding. sgRNA was covalently labeled with fluorescein to provide fluorescence signal. Graphene oxide (GO) is utilized for its quenching properties …


Synthesis And Biological Evaluation Of Grp94 Selective Inhibitors, Zach Priebe, Kyler Pugh, Brian S. J. Blagg Jan 2021

Synthesis And Biological Evaluation Of Grp94 Selective Inhibitors, Zach Priebe, Kyler Pugh, Brian S. J. Blagg

Summer Research

Grp94 is one of four chaperones which belong to the Heat Shock Protein 90 (Hsp90) family. Hsp90 isoforms exist as homodimers and assist in the folding and maturation of over 400 client proteins. These proteins are highly sought-after therapeutic targets as they are known to chaperone misfolded proteins involved in various signaling pathways. During the protein folding cycle, ATP binds to the N-Terminal domain of Hsp90, which allows nascent polypeptides to undergo maturation. To prevent the folding and maturation of oncogenic proteins, researchers developed N-terminal inhibitors to prevent ATP binding. Unfortunately, these inhibitors (termed pan-inhibitors) were not isoform selective, which …


Substrate Profiling Of The Epigenetic Erasers Hdac1 And Lsd1, Herath Mudiyansela Gedara Kavinda Eranga Herath Jan 2021

Substrate Profiling Of The Epigenetic Erasers Hdac1 And Lsd1, Herath Mudiyansela Gedara Kavinda Eranga Herath

Wayne State University Dissertations

Regulators of chromatin structure have emerged as a key driver of transcriptional responses inside the cell. Two such groups of regulators, histone writers and erasers; the proteins, that add or remove histone post translational modifications (PTMs), have become the central players in chromatin structure. Thus, the aberrant expression of writers and erasures is a hallmark in human diseases. For example, overexpression of the erasures histone deacetylase1 (HDAC1) and lysine specific demethylase1 (LSD1) had been reported in many cancers. Currently, HDAC inhibitors have been used successfully for cancer treatment and several inhibitors targeting LSD1 are in clinical trial. To date, apart …


Developing Inhibitors Of Uchl5 Deubiquitinase In The Proteasome, Harshani Sewvandi Gurusingha Arachchige Jan 2021

Developing Inhibitors Of Uchl5 Deubiquitinase In The Proteasome, Harshani Sewvandi Gurusingha Arachchige

Wayne State University Dissertations

Ubiquitin proteasomal system (UPS) plays a vital role in maintaining protein homeostasis by eliminating misfolded and damaged proteins in a eukaryotic cell. Target proteins to be degraded are modified by poly-ubiquitination, which leads to degradation by 26S proteasome. Before entering the 20S catalytic subunit, the 19S regulatory particle is responsible for binding, unfolding, and deubiquitinating the target protein. Based on the nature of the polyubiquitin tag, removal of the ubiquitin is performed by the deubiquitinases (DUBs) associated with the proteasome.Ubiquitin carboxyl-terminal hydrolase isozyme L5 (UCHL5) is one of the three DUBs in the proteasome. UCHL5 regulates many cellular functions and …


Integrative Network Analyses Of Transcriptomics Data Reveal Potential Drug Targets For Acute Radiation Syndrome, Robert Moore, Bhanwar Lal Puniya, Robert Powers, Chittibabu Guda, Kenneth W. Bayles, David Berkowitz, Tomas Helikar Jan 2021

Integrative Network Analyses Of Transcriptomics Data Reveal Potential Drug Targets For Acute Radiation Syndrome, Robert Moore, Bhanwar Lal Puniya, Robert Powers, Chittibabu Guda, Kenneth W. Bayles, David Berkowitz, Tomas Helikar

Department of Biochemistry: Faculty Publications

Recent political unrest has highlighted the importance of understanding the short- and long-term effects of gamma-radiation exposure on human health and survivability. In this regard, effective treatment for acute radiation syndrome (ARS) is a necessity in cases of nuclear disasters. Here, we propose 20 therapeutic targets for ARS identified using a systematic approach that integrates gene co-expression networks obtained under radiation treatment in humans and mice, drug databases, disease-gene association, radiation-induced differential gene expression, and literature mining. By selecting gene targets with existing drugs, we identified potential candidates for drug repurposing. Eight of these genes (BRD4, NFKBIA, CDKN1A, TFPI, MMP9, …


Root Nrt, Nir, Amt, Gs, Gogat And Gdh Expression Levels Reveal No Andaba Mediated Drought Tolerance In Brassica Juncea L., Seema Sahay, Luis Robledo-Arratia, Katarzyna Glowacka, Meetu Gupta Jan 2021

Root Nrt, Nir, Amt, Gs, Gogat And Gdh Expression Levels Reveal No Andaba Mediated Drought Tolerance In Brassica Juncea L., Seema Sahay, Luis Robledo-Arratia, Katarzyna Glowacka, Meetu Gupta

Department of Biochemistry: Faculty Publications

Little is known about the interactive effects of exogenous nitric oxide (NO) and abscisic acid (ABA) on nitrogen (N) metabolism and related changes at molecular and biochemical levels under drought stress. The present study highlights the independent and combined effect of NO and ABA (grouped as “nitrate agonists”) on expression profiles of representative key genes known to be involved in N-uptake and assimilation, together with proline metabolism, N–NO metabolism enzyme’s activity and nutrient content in polyethylene glycol (PEG) treated roots of Indian mustard (B. juncea cv. Varuna). Here we report that PEG mediated drought stress negatively inhibited growth performance, as …


The Inhibition Of Growth Of S. Cerevisiae, U. Maydis, And M. Lychinidis-Dioicae By Apiaecea Plant Extracts, Jackson M Hoffman, Jared Scott, David Schultz Phd Jan 2021

The Inhibition Of Growth Of S. Cerevisiae, U. Maydis, And M. Lychinidis-Dioicae By Apiaecea Plant Extracts, Jackson M Hoffman, Jared Scott, David Schultz Phd

Undergraduate Arts and Research Showcase

The Apiaceae family of plants contains over 3,500 species, many of which are used as food crops: vegetables (carrot, parsnip, celery, etc.), herbs (cilantro, fennel, dill, etc.), and spices (cumin, anise, caraway, etc.). Many spices have been shown to exhibit antimicrobial properties against both bacteria and fungi. We set out to determine if the Apiaceae spice extracts currently used in our lab for anticancer studies exhibit any antimicrobial properties. Ethanolic extracts were made from several Apiaceae seeds: Apium graveolens (celery), Cuminum cyminum (cumin), Anethum graveolens(dill), Foeniculum vulgare (fennel), Coriandrum satvium (coriander), Pimpinella ansium (anise), Trachyspermum ammi (ajwain), Carum carvi …


An In Vivo Inducible Expression System To Determine Antibacterial Activity Of Peptides, Rabiul Islam Jan 2021

An In Vivo Inducible Expression System To Determine Antibacterial Activity Of Peptides, Rabiul Islam

Wayne State University Dissertations

The threat of bacterial resistance throughout the world has created tremendous challenges to clinicians. Some bacterial species have acquired resistance to not only single antibiotics, but also to multiple compounds, which is called multidrug resistance. Since the early discovery of resistance to penicillin, scientists have been developing new drugs to combat antibiotic resistance. In some cases, it took less than a decade to develop resistance to a new antibiotic. The World Health Organization (WHO) reported several deadly multi-drug-resistant bacteria, some of which cause life-threating illnesses. Each year more than 35,000 people in the United States die from antibiotic-resistant bacterial infections. …


Machine Learning And Bioinformatic Insights Into Key Enzymes For A Bio-Based Circular Economy, Japheth E. Gado Jan 2021

Machine Learning And Bioinformatic Insights Into Key Enzymes For A Bio-Based Circular Economy, Japheth E. Gado

Theses and Dissertations--Chemical and Materials Engineering

The world is presently faced with a sustainability crisis; it is becoming increasingly difficult to meet the energy and material needs of a growing global population without depleting and polluting our planet. Greenhouse gases released from the continuous combustion of fossil fuels engender accelerated climate change, and plastic waste accumulates in the environment. There is need for a circular economy, where energy and materials are renewably derived from waste items, rather than by consuming limited resources. Deconstruction of the recalcitrant linkages in natural and synthetic polymers is crucial for a circular economy, as deconstructed monomers can be used to manufacture …


The Phylogenetic Analysis Of Genes Encoding Specific Steps In The Glutathione Pathway Within Industrial Beer Brewing Strains: Saccharomyces Cerevisiae, Saccharomyces Pastorinus, And The Spoilage Microbe Brettanomyces, Miles Tyler Johnson Jan 2021

The Phylogenetic Analysis Of Genes Encoding Specific Steps In The Glutathione Pathway Within Industrial Beer Brewing Strains: Saccharomyces Cerevisiae, Saccharomyces Pastorinus, And The Spoilage Microbe Brettanomyces, Miles Tyler Johnson

Online Theses and Dissertations

The Glutathione pathway, (GSH) is an antioxidant system in yeast that increases cell viability and contributes to the production of desirable beer flavors during industrial fermentation. Despite its importance, studies using the GSH pathway: GSH1, GSH2, GLR1, and SOD1 genes, to trace the evolutionary history of beer strains are lacking. As a result, the investigator sought to elucidate the phylogenetic relationships between four commonly used industrial beer strains: California Ale, London Ale, Oktoberfest, and Brettanomyces bruxellensis through single-gene sequencing analysis of the GSH pathway. It was hypothesized that the actions of these GSH genes are unique and potentially upregulated in …


How Does Atg 10 Regulate The Autophagic Process? An Investigation Into The Atg12-5 Conjugation Pathway, Ayanda Brydie Jan 2021

How Does Atg 10 Regulate The Autophagic Process? An Investigation Into The Atg12-5 Conjugation Pathway, Ayanda Brydie

Senior Honors Theses and Projects

Autophagy is a highly conserved eukaryotic cellular recycling process in which the degradation of proteins and cytoplasmic organelles occurs to recycle broken down products throughout the cell. This process plays a critical role in cell survival and maintenance. Once initiated by either nutrient deficiency (bulk autophagy) or recognition of damaged organelles (selective autophagy) this process is mediated by autophagy-related proteins (Atg proteins). The Atg proteins function to form a double-membrane vesicle, the autophagosome, to target part of the cytoplasm and deliver it to the vesicle for breakdown. In bulk autophagy, the presence of these proteins at the phagophore assembly site …


Structural Analysis Of Neutralizing Epitopes Of The Sars-Cov-2 Spike To Guide Therapy And Vaccine Design Strategies, Maxwell T. Finkelstein , '22, Adam G. Mermelstein , '21, Emma Parker Miller , '22, Paul C. Seth , '22, Erik-Stephane D. Stancofski , '21, Daniela Fera Jan 2021

Structural Analysis Of Neutralizing Epitopes Of The Sars-Cov-2 Spike To Guide Therapy And Vaccine Design Strategies, Maxwell T. Finkelstein , '22, Adam G. Mermelstein , '21, Emma Parker Miller , '22, Paul C. Seth , '22, Erik-Stephane D. Stancofski , '21, Daniela Fera

Chemistry & Biochemistry Faculty Works

Coronavirus research has gained tremendous attention because of the COVID-19 pandemic, caused by the novel severe acute respiratory syndrome coronavirus (nCoV or SARS-CoV-2). In this review, we highlight recent studies that provide atomic-resolution structural details important for the development of monoclonal antibodies (mAbs) that can be used therapeutically and prophylactically and for vaccines against SARS-CoV-2. Structural studies with SARS-CoV-2 neutralizing mAbs have revealed a diverse set of binding modes on the spike’s receptor-binding domain and N-terminal domain and highlight alternative targets on the spike. We consider this structural work together with mAb effects in vivo to suggest correlations between structure …


Purification And Activity Analysis Of A Highly Active Recombinant Catalase From Psychrophilic Bacterium Psychrobacter Cryohaloentis, Andrew Stewart Jan 2021

Purification And Activity Analysis Of A Highly Active Recombinant Catalase From Psychrophilic Bacterium Psychrobacter Cryohaloentis, Andrew Stewart

Honors Program Theses

To date, the genus Psychrobacter includes 37 recognized bacterial species isolated from different sources ranging from Siberian permafrost (P. cryohalolentis) to seal feces (P. lutiphocae). Due to its diverse ecological niches, several species belonging to the genus have different enzymatic activities with potential applications in bioremediation and the food industry. In this study, a bioprospecting approach was used to perform a in depth analysis of a Psychrobacter-like bacterial strain isolated from goose feces (designated as Psychrobacter unknown). The phylogenetic analysis of 16S rRNA gene and homologous sequence studies suggest that the strain may represent a novel species of the Psychrobacter …


High Throughput Analysis To Study Emerging Pollutants And Nanoparticle Fate In Biological Systems, Xiaolong He Jan 2021

High Throughput Analysis To Study Emerging Pollutants And Nanoparticle Fate In Biological Systems, Xiaolong He

Doctoral Dissertations

”The increasing applications of emerging and fugitive contaminants (EFCs) and engineered nanoparticles (ENPs) attract significant research interest for their potential risks to human health and the environment. In order to assess the health risks of these emerging contaminants, rapid and reliable analytical methods to measure the concentrations and fates of these contaminants are imperative. This dissertation focuses on the developments of advanced analytical methods and their applications to study those emerging contaminants in crop plant and simulated gastric fluid (SGF). Three types of mass spectrometry based methodologies have been developed, one is freeze-thaw/centrifugation extraction followed by high performance liquid chromatography …


Lysosomal Slc46a3 Modulates Hepatic Cytosolic Copper Homeostasis, Jung-Hwan Kim, Tsutomu Matsubara, Jaekwom Lee, Cristina Fenollar-Ferrer, Kyungreem Han, Donghwan Kim, Shang Jia, Christopher J. Chang, Heejung Yang, Tomokazu Nagano, Kristopher W. Krausz, Sun Hee Yim, Frank J. Gonzalez Jan 2021

Lysosomal Slc46a3 Modulates Hepatic Cytosolic Copper Homeostasis, Jung-Hwan Kim, Tsutomu Matsubara, Jaekwom Lee, Cristina Fenollar-Ferrer, Kyungreem Han, Donghwan Kim, Shang Jia, Christopher J. Chang, Heejung Yang, Tomokazu Nagano, Kristopher W. Krausz, Sun Hee Yim, Frank J. Gonzalez

Department of Biochemistry: Faculty Publications

The environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes hepatic toxicity associated with prominent lipid accumulation in humans. Here, the authors report that the lysosomal copper transporter SLC46A3 is induced by TCDD and underlies the hepatic lipid accumulation in mice, potentially via effects on mitochondrial function. SLC46A3 was localized to the lysosome where it modulated intracellular copper levels. Forced expression of hepatic SLC46A3 resulted in decreased mitochondrial membrane potential and abnormal mitochondria morphology consistent with lower copper levels. SLC46A3 expression increased hepatic lipid accumulation similar to the known effects of TCDD exposure in mice and humans. The TCDD-induced hepatic triglyceride accumulation was significantly …


The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes Jan 2021

The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes

Honors Theses

The internal recycling phosphorus in freshwater lake bottom sediments represents a significant source of hypolimnetic phosphorus (P) release for many of Maine’s lakes. In summer months, Maine lakes often thermally stratify and the lake hypolimnion develops anoxia, leading to a reduction in redox potential at the sediment-water interface. These reducing conditions facilitate the reductive dissolution of ferric iron, and, since phosphorus is often present in freshwater lake sediments as solid FeOOH-PO4 complexes, results in release of soluble phosphorus into the water column. Our current study presents field and laboratory data from sediment fractionation extractions designed to quantify concentrations of …


Photoreceptor Phosphodiesterase (Pde6): Activation And Inactivation Mechanisms During Visual Transduction In Rods And Cones, Rick H. Cote Jan 2021

Photoreceptor Phosphodiesterase (Pde6): Activation And Inactivation Mechanisms During Visual Transduction In Rods And Cones, Rick H. Cote

Faculty Publications

Rod and cone photoreceptors of the vertebrate retina utilize cGMP as the primary

intracellular messenger for the visual signaling pathway that converts a light stimulus into an electrical response. cGMP metabolism in the signal-transducing photoreceptor outer segment reflects the balance of cGMP synthesis (catalyzed by guanylyl cyclase) and degradation (catalyzed by the photoreceptor phosphodiesterase, PDE6). Upon light stimulation, rapid activation of PDE6 by the heterotrimeric G-protein (transducin) triggers a dramatic drop in cGMP levels that lead to cell hyperpolarization. Following cessation of the light stimulus, the lifetime of activated PDE6 is also precisely regulated by additional processes. This review summarizes …


Photoreceptor Phosphodiesterase (Pde6): Structure, Regulatory Mechanisms, And Implications For Treatment Of Retinal Diseases, Rick H. Cote, Richa Gupta, Michael J. Irwin, Xin Wang Jan 2021

Photoreceptor Phosphodiesterase (Pde6): Structure, Regulatory Mechanisms, And Implications For Treatment Of Retinal Diseases, Rick H. Cote, Richa Gupta, Michael J. Irwin, Xin Wang

Faculty Publications

The photoreceptor phosphodiesterase (PDE6) is a member of large family of Class I phosphodiesterases responsible for hydrolyzing the second messengers cAMP and cGMP. PDE6 consists of two catalytic subunits and two inhibitory subunits that form a tetrameric protein. PDE6 is a peripheral membrane protein that is localized to the signaling-transducing compartment of rod and cone photoreceptors. As the central effector enzyme of the G-protein coupled visual transduction pathway, activation of PDE6 catalysis causes in a rapid decrease in cGMP levels that results in closure of cGMP-gated ion channels in the photoreceptor plasma membrane. Because of its importance in the phototransduction …


Use Of Small Molecule Fanconi Anemia Pathway Inhibitors As Sensitizing Agents To Laromustine., Sam W. Marchant Jan 2021

Use Of Small Molecule Fanconi Anemia Pathway Inhibitors As Sensitizing Agents To Laromustine., Sam W. Marchant

Honors Theses

Laromustine is an experimental chemotherapeutic sulfonyl hydrazine prodrug shown in clinical trials to be effective against acute myeloid leukemia. The mechanism of action of laromustine involves interstrand crosslinking, via chloroethylation, and enzyme inhibition, caused by carbamoylation. The work described herein aims to investigate whether inhibition of the replication-dependent interstrand crosslink repair Fanconi Anemia pathway further sensitizes cells to laromustine. By measuring metabolic activity immediately after drug exposure, we find laromustine to be equally as cytotoxic towards Fanconi Anemia deficient and wild type cells. However, through clonogenic assays we show Fanconi Anemia mutations sensitize cells to laromustine’s anti-proliferative effect. Furthermore, we …