Other Biochemistry, Biophysics, and Structural Biology Commons^™

Crispr/Cas9-Induced Fad2 And Rod1 Mutations Stacked With Fae1 Confer High Oleic Acid Seed Oil In Pennycress (Thlaspi Arvense L.), Brice A. Jarvis, Trevor B. Romsdahl, Michaela G. Mcginn, Tara J. Nazarenus, Edgar B. Cahoon, Kent D. Chapman, John C. Sedbrook

Department of Biochemistry: Faculty Publications

Pennycress (Thlaspi arvense L.) is being domesticated as an oilseed cash cover crop to be grown in the off-season throughout temperate regions of the world. With its diploid genome and ease of directed mutagenesis using molecular approaches, pennycress seed oil composition can be rapidly tailored for a plethora of food, feed, oleochemical and fuel uses. Here, we utilized Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 technology to produce knockout mutations in the FATTY ACID DESATURASE2 (FAD2) and REDUCED OLEATE DESATURATION1 (ROD1) genes to increase oleic acid content. High oleic acid (18:1) oil is valued for its oxidative stability that is …

Isoprene Production From Municipal Wastewater Biosolids By Engineered Archaeon Methanosarcina Acetivorans, Sean Carr, Jared Aldridge, Nicole R. Buan

Department of Biochemistry: Faculty Publications

Wastewater biosolids are a promising feedstock for production of value-added renewable chemicals. Methane-producing archaea (methanogens) are already used to produce renewable biogas via the anaerobic treatment of wastewater. The ability of methanogens to efficiently convert dissolved organic carbon into methane makes them an appealing potential platform for biorefining using metabolic engineering. We have engineered a strain of the methanogen Methanosarcina acetivorans to produce the volatile hemiterpene isoprene in addition to methane. The engineered strain was adapted to grow in municipal wastewater through cultivation in a synthetic wastewater medium. When introduced to municipal wastewater the engineered methanogens were able to compete …

Isoprene Production From Municipal Wastewater Biosolids By Engineered Archaeon Methanosarcina Acetivorans, Sean Carr, Jared Aldridge, Nicole R. Buan

Department of Biochemistry: Faculty Publications

Wastewater biosolids are a promising feedstock for production of value-added renewable chemicals. Methane-producing archaea (methanogens) are already used to produce renewable biogas via the anaerobic treatment of wastewater. The ability of methanogens to efficiently convert dissolved organic carbon into methane makes them an appealing potential platform for biorefining using metabolic engineering. We have engineered a strain of the methanogen Methanosarcina acetivorans to produce the volatile hemiterpene isoprene in addition to methane. The engineered strain was adapted to grow in municipal wastewater through cultivation in a synthetic wastewater medium. When introduced to municipal wastewater the engineered methanogens were able to compete …

Structural Basis For Clostridium Perfringens Enterotoxin Targeting Of Claudins At Tight Junctions In Mammalian Gut, Alex J. Vecchio, Sewwandi S. Rathnayake, Robert M. Stroud

Department of Biochemistry: Faculty Publications

The bacterium Clostridium perfringens causes severe, sometimes lethal gastrointestinal disorders in humans, including enteritis and enterotoxemia. Type F strains produce an enterotoxin (CpE) that causes the third most common foodborne illness in the United States. CpE induces gut breakdown by disrupting barriers at cell–cell contacts called tight junctions (TJs), which are formed and maintained by claudins. Targeted binding of CpE to specific claudins, encoded by its C-terminal domain (cCpE), loosens TJ barriers to trigger molecular leaks between cells. Cytotoxicity results from claudin-bound CpE complexes forming pores in cell membranes. In mammalian tissues, ∼24 claudins govern TJ barriers—but the basis for …

Case 32: Inhibition Of Protein Tyrosine Phosphatase Enzymes As A Possible Treatment For Diabetes, Dr. Kathleen Cornely

Chemistry & Biochemistry Case Studies

Protein tyrosine phosphatases (PTPs) are investigated because of their ability to reverse the effects of protein tyrosine kinases (PTKs). Inhibitors of the PTP investigated in this study have insulin-mimetic effects and have potential in the treatment of diabetes.

Highlighting Membrane Protein Structure And Function: A Celebration Of The Protein Data Bank, Fei Li, Pascal F. Egea, Alex J. Vecchio, Ignacio Asial, Meghna Gupta, Joana Paulino, Ruchika Bajaj, Miles Sasha Dickinson, Shelagh Fergunson-Miller, Brian C. Monk, Robert M. Stroud

Department of Biochemistry: Faculty Publications

Biological membranes define the boundaries of cells and compartmentalize the chemical and physical processes required for life. Many biological processes are carried out by proteins embedded in or associated with such membranes. Determination of membrane protein (MP) structures at atomic or near-atomic resolution plays a vital role in elucidating their structural and functional impact in biology. This endeavor has determined 1198 unique MP structures as of early 2021. The value of these structures is expanded greatly by deposition of their three-dimensional (3D) coordinates into the Protein Data Bank (PDB) after the first atomic MP structure was elucidated in 1985. Since …

A Co-Opted Steroid Synthesis Gene, Maintained In Sorghum But Not Maize, Is Associated With A Divergence In Leaf Wax Chemistry, Lucas Busta, Elizabeth Schmitz, Dylan K. Kosma, James Schnable, Edgar B. Cahoon

Department of Biochemistry: Faculty Publications

Virtually all land plants are coated in a cuticle, a waxy polyester that prevents nonstomatal water loss and is important for heat and drought tolerance. Here, we describe a likely genetic basis for a divergence in cuticular wax chemistry between Sorghum bicolor, a drought tolerant crop widely cultivated in hot climates, and its close relative Zea mays (maize). Combining chemical analyses, heterologous expression, and comparative genomics, we reveal that: 1) sorghum and maize leaf waxes are similar at the juvenile stage but, after the juvenile-to-adult transition, sorghum leaf waxes are rich in triterpenoids that are absent from maize; 2) …

Cown Sustains Nitrogenase Turnover In The Presence Of The Inhibitor Carbon Monoxide, Michael S. Medina, Kevin O. Bretzing, Richard A. Aviles, Kiersten M. Chong, Alejandro Espinoza, Chloe Nicole G. Garcia, Benjamin B. Katz, Ruchita N. Kharwa, Andrea Hernandez, Justin L. Lee, Terrence M. Lee, Christine Lo Verde, Max W. Strul, Emily Y. Wong, Cedric P. Owens

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Nitrogenase is the only enzyme capable of catalyzing nitrogen fixation, the reduction of dinitrogen gas (N₂) to ammonia (NH₃). Nitrogenase is tightly inhibited by the environmental gas carbon monoxide (CO). Nitrogen-fixing bacteria rely on the protein CowN to grow in the presence of CO. However, the mechanism by which CowN operates is unknown. Here, we present the biochemical characterization of CowN and examine how CowN protects nitrogenase from CO. We determine that CowN interacts directly with nitrogenase and that CowN protection observes hyperbolic kinetics with respect to CowN concentration. At a CO concentration of 0.001 atm, …

Structural Basis For Clostridium Perfringens Enterotoxin Targeting Of Claudins At Tight Junctions In Mammalian Gut, Alex J. Vecchio, Sewwandi S. Rathnayake, Robert M. Stroud

Department of Biochemistry: Faculty Publications

The bacterium Clostridium perfringens causes severe, sometimes lethal gastrointestinal disorders in humans, including enteritis and enterotoxemia. Type F strains produce an enterotoxin (CpE) that causes the third most common foodborne illness in the United States. CpE induces gut breakdown by disrupting barriers at cell–cell contacts called tight junctions (TJs), which are formed and maintained by claudins. Targeted binding of CpE to specific claudins, encoded by its C-terminal domain (cCpE), loosens TJ barriers to trigger molecular leaks between cells. Cytotoxicity results from claudin-bound CpE complexes forming pores in cell membranes. In mammalian tissues, 24 claudins govern TJ barriers—but the basis for …

Case 70: Hemoglobin Mito: A Japanese Hemoglobin Variant With Altered Oxygen Binding Affinity, Dr. Kathleen Cornely

Chemistry & Biochemistry Case Studies

In this case study, researchers use their knowledge of hemoglobin structure to predict the oxygen binding properties of a hemoglobin mutant with a single amino acid substitution, then test their hypothesis by studying the mutant’s oxygen binding properties.

Mutational And Biophysical Robustness In A Prestabilized Monobody, Peter G. Chandler, Li Lynn Tan, Benjamin T. Porebski, James S. Green, Blake T. Riley, Sebastian S. Broendum, David E. Hoke, Robert J. Falconer, Trent P. Munro, Malcolm Buckle, Colin J. Jackson, Ashley M. Buckle

Advanced Science Research Center

The fibronectin type III (FN3) monobody domain is a promising non-antibody scaffold, which features a less complex architecture than an antibody while maintaining analogous binding loops. We previously developed FN3Con, a hyperstable monobody derivative with diagnostic and therapeutic potential. Prestabilization of the scaffold mitigates the stability–function trade-off commonly associated with evolving a protein domain toward biological activity. Here, we aimed to examine if the FN3Con monobody could take on antibody-like binding to therapeutic targets, while retaining its extreme stability. We targeted the first of the Adnectin derivative of monobodies to reach clinical trials, which was engineered by directed evolution for …

Protease Oma1 Modulates Mitochondrial Bioenergetics And Ultrastructure Through Dynamic Association With Micos Complex, Martonio Ponte Viana, Roman M. Levytskyy, Ruchika Anand, Andreas S. Reichert, Oleh Khalimonchuk

Department of Biochemistry: Faculty Publications

Remodeling of mitochondrial ultrastructure is a process that is critical for organelle physiology and apoptosis. Although the key players in this process—mitochondrial contact site and cristae junction organizing system (MICOS) and Optic Atrophy 1 (OPA1)—have been characterized, the mechanisms behind its regulation remain incompletely defined. Here, we found that in addition to its role in mitochondrial division, metallopeptidase OMA1 is required for the maintenance of intermembrane connectivity through dynamic association with MICOS. This association is independent of OPA1, mediated via the MICOS subunit MIC60, and is important for stability of MICOS and the intermembrane contacts. The OMA1-MICOS relay is required …

Generating Pennycress (Thlaspi Arvense) Seed Triacylglycerols And Acetyl-Triacylglycerols Containing Medium-Chain Fatty Acids, Maliheh Esfahanian, Tara J. Nazarenus, Meghan M. Freund, Gary Mcintosh, Winthrop B. Phippen, Mary E. Phippen, Timothy P. Durrett, Edgar B. Cahoon, John C. Sedbrook

Department of Biochemistry: Faculty Publications

Thlaspi arvense L. (pennycress) is a cold-tolerant Brassicaceae that produces large amounts of seeds rich in triacylglycerols and protein, making it an attractive target for domestication into an offseason oilseed cash cover crop. Pennycress is easily genetically transformed, enabling synthetic biology approaches to tailor oil properties for specific biofuel and industrial applications. To test the feasibility in pennycress of producing TAGs and acetyl-TAGs rich in medium-chain fatty acids (MCFAs; C6–C14) for industrial, biojet fuel and improved biodiesel applications, we generated transgenic lines with seed-specific expression of unique acyltransferase (LPAT and diacylglycerol acyltransferase) genes and thioesterase (FatB) genes isolated from Cuphea …

Genetic Engineering Of Lesquerella With Increased Ricinoleic Acid Content In Seed Oil, Grace Q. Chen, Kumiko Johnson, Tara J. Nazarenus, Grisel Ponciano, Eva Morales, Edgar B. Cahoon

Department of Biochemistry: Faculty Publications

Seeds of castor (Ricinus communis) are enriched in oil with high levels of the industrially valuable fatty acid ricinoleic acid (18:1OH), but production of this plant is limited because of the cooccurrence of the ricin toxin in its seeds. Lesquerella (Physaria fendleri) is being developed as an alternative industrial oilseed because its seeds accumulate lesquerolic acid (20:1OH), an elongated form of 18:1OH in seed oil which lacks toxins. Synthesis of 20:1OH is through elongation of 18:1OH by a lesquerella elongase, PfKCS18. Oleic acid (18:1) is the substrate for 18:1OH synthesis, but it is also used by fatty acid desaturase 2 …

Long Non-Coding Rna Meg3 Deficiency Impairs Glucose Homeostasis And Insulin Signaling By Inducing Cellular Senescence Of Hepatic Endothelium In Obesity, Xiao Cheng, Mohamed Sham Shihabudeen Haider Ali, Matthew Moran, Martonio Ponte Viana, Sarah L. Schlichte, Matthew C. Zimmerman, Oleh Khalimonchuk, Mark W. Feinberg, Xinghui Sun

Department of Biochemistry: Faculty Publications

Obesity-induced insulin resistance is a risk factor for diabetes and cardiovascular disease. However, the mechanisms underlying endothelial senescence in obesity, and how it impacts obesity-induced insulin resistance remain incompletely understood. In this study, transcriptome analysis revealed that the long non-coding RNA (lncRNA) Maternally expressed gene 3 (Meg3) is one of the top differentially expressed lncRNAs in the vascular endothelium in diet-induced obese mice. Meg3 knockdown induces cellular senescence of endothelial cells characterized by increased senescence-associated β–galactosidase activity, increased levels of endogenous superoxide, impaired mitochondrial structure and function, and impaired autophagy. Moreover, Meg3 knockdown causes cellular senescence of hepatic endothelium in …

Design Of Fibril Forming Collagen Mimetic Peptides: Heterotrimers And Nucleation Domains, Sally Tan

Theses and Dissertations

This paper attempts to design collagen mimetic peptides where the triple-helical region mimics that of human Type I Collagen. With consideration for chain selection and chain register, we utilize the NC2 domain of heterotrimeric Type IX Collagen as a nucleation domain for triple-helix folding.

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 …

Open Neuroscience Initiative, Austin Lim

College of Science and Health Full Text Publications

The Open Neuroscience Initiative is a free-to-use textbook

This project began as a means to overcoming the financial burden that face undergraduate neuroscience students when buying textbooks. By compiling and writing a completely free-to-access textbook that covers the foundations of a typical college introduction to neuroscience course, students would have one less obstacle to overcome in their educational career, allowing them to focus their valuable time and attention on learning rather than finances. To make this project a reality, I began with a humble tweet in May 2019 that managed to gain a tiny bit of traction among the neuroscience …

Teaching Metabolism In Upper-Division Undergraduate Biochemistry Courses Using Online Computational Systems And Dynamical Models Improves Student Performance, Christine S. Booth, Changsoo Song, Michelle E. Howell, Achilles Rasquinha, Aleš Saska, Resa M. Helikar, Sharmin M. Sikich, Brain A. Couch, Karin Van Dijk, Rebecca Roston, Tomáš Helikar

Department of Biochemistry: Faculty Publications

Understanding metabolic function requires knowledge of the dynamics, interdependence, and regulation of metabolic networks. However, multiple professional societies have recognized that most undergraduate biochemistry students acquire only a surface-level understanding of metabolism. We hypothesized that guiding students through interactive computer simulations of metabolic systems would increase their ability to recognize how individual interactions between components affect the behavior of a system under different conditions. The computer simulations were designed with an interactive activity (i.e., module) that used the predict–observe–explain model of instruction to guide students through a process in which they iteratively predict outcomes, test their predictions, modify the interactions …

Long Non-Coding Rna Meg3 Deficiency Impairs Glucose Homeostasis And Insulin Signaling By Inducing Cellular Senescence Of Hepatic Endothelium In Obesity, Xiao Cheng, Mohamed Sham Shihabudeen Haider Ali, Matthew Moran, Martonio Ponte Viana, Sarah L. Schlichte, Matthew C. Zimmerman, Oleh Khalimonchuk, Mark W. Feinberg, Xinghui Sun

Department of Biochemistry: Faculty Publications

Obesity-induced insulin resistance is a risk factor for diabetes and cardiovascular disease. However, the mechanisms underlying endothelial senescence in obesity, and how it impacts obesity-induced insulin resistance remain incompletely understood. In this study, transcriptome analysis revealed that the long non-coding RNA (lncRNA) Maternally expressed gene 3 (Meg3) is one of the top differentially expressed lncRNAs in the vascular endothelium in diet-induced obese mice. Meg3 knockdown induces cellular senescence of endothelial cells characterized by increased senescence-associated β–galactosidase activity, increased levels of endogenous superoxide, impaired mitochondrial structure and function, and impaired autophagy. Moreover, Meg3 knockdown causes cellular senescence of hepatic endothelium in …

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

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 …

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 …

Covid19 Disease Map, A Computational Knowledge Repository Of Virus–Host Interaction Mechanisms, Marek Ostaszewski, Tomáš Helikar, Bhanwar Lal Puniya, A Host Of Co-Authors, Covid-19 Disease Map Community

Department of Biochemistry: Faculty Publications

We need to effectively combine the knowledge from surging literature with complex datasets to propose mechanistic models of SARS-CoV-2 infection, improving data interpretation and predicting key targets of intervention. Here, we describe a large-scale community effort to build an open access, interoperable and computable repository of COVID-19 molecular mechanisms. The COVID-19 Disease Map (C19DMap) is a graphical, interactive representation of disease-relevant molecular mechanisms linking many knowledge sources. Notably, it is a computational resource for graph-based analyses and disease modelling. To this end, we established a framework of tools, platforms and guidelines necessary for a multifaceted community of biocurators, domain experts, …

Association Of The Malate Dehydrogenase‑Citrate Synthase Metabolon Is Modulated By Intermediates Of The Krebs Tricarboxylic Acid Cycle, Joy Omini, Izabela Wojciechowska, Aleksandra Skirycz, Hideaki Moriyama, Toshihiro Obata

Department of Biochemistry: Faculty Publications

Mitochondrial malate dehydrogenase (MDH)-citrate synthase (CS) multi-enzyme complex is a part of the Krebs tricarboxylic acid (TCA) cycle ‘metabolon’ which is enzyme machinery catalyzing sequential reactions without diffusion of reaction intermediates into a bulk matrix. This complex is assumed to be a dynamic structure involved in the regulation of the cycle by enhancing metabolic flux. Microscale Thermophoresis analysis of the porcine heart MDH-CS complex revealed that substrates of the MDH and CS reactions, NAD+ and acetyl-CoA, enhance complex association while products of the reactions, NADH and citrate, weaken the affinity of the complex. Oxaloacetate enhanced the interaction only when it …

The Need For Research-Grade Systems Modeling Technologies For Life Science Education, Tomáš Helikar

Department of Biochemistry: Faculty Publications

The coronavirus disease 2019 (COVID-19) pandemic not only challenged deeply-rooted daily patterns but also put a spotlight on the role of computational modeling in science and society. Amid the impromptu upheaval of in-person education across the world, this article aims to articulate the need to train students in computational and systems biology using research-grade technologies. ...

Life sciences education needs multiple technical infrastructures explicitly designed to support this field’s vast computational needs. Developing and sustaining effective, scientifically authentic educational technologies is not easy. It requires expertise in software development and the scientific domain as well as in education and education …

Development Of Fluorescence Microscopy Approaches To Study Subcellular Protein Transport And Enzymatic Activity, Anchal Singh

Masters Theses

Understanding the subcellular localization of proteins and their activity is important in understanding their normal function in eukaryotic cells. Fluorescence cellular imaging techniques can selectively and sensitively visualize subcellular biochemistry. Using this approach, two different methods were employed in this thesis. The first focused on studying protein import into peroxisome and the other on monitoring the activity of an endoplasmic reticulum (ER)-localized enzyme, human carboxylesterase 1 (CES1).

Peroxisomes are mainly known as the center for long chain fatty acid b-oxidation as well as the production and detoxification of hydrogen peroxide. Proteins which are needed in the peroxisomes are encoded in …

Monitoring Stem Cell Differentiation Using Raman Microspectroscopy: Chondrogenic Differentiation, Towards Cartilage Formation, Francesca Ravera, Esen Efeoglu, Hugh Byrne

Articles

Mesenchymal Stem Cells (MSCs) have the ability to differentiate into chondrocytes, the only cellular components of cartilage and are therefore ideal candidates for cartilage and tissue repair technologies. Chondrocytes are surrounded by cartilage-like extracellular matrix (ECM), a complex network rich in glycosaminoglycans, proteoglycans, and collagen, which, together with a multitude of intracellular signalling molecules, trigger the chondrogenesis and allow the chondroprogenitor to acquire the spherical morphology of the chondrocytes. However, although the mechanisms of the differentiation of MSCs have been extensively explored, it has been difficult to provide a holistic picture of the process, in situ. Raman Micro Spectroscopy (RMS) …