Biochemistry, Biophysics, and Structural Biology Commons^™

Sterol Biosynthesis In Four Green Algae: A Bioinformatic Analysis Of The Ergosterol Versus Phytosterol Decision Point, Adam Voshall, Nakeirah T.M. Christie, Suzanne L. Rose, Maya Khasin, James L. Van Etten, Jennifer E. Markham, Wayne R. Riekhof, Kenneth Nickerson

School of Biological Sciences: Faculty Publications

Animals and fungi produce cholesterol and ergosterol, respectively, while plants produce the phytosterols stigmasterol, campesterol, and bsitosterol in various combinations. The recent sequencing of many algal genomes allows the detailed reconstruction of the sterol metabolic pathways. Here, we characterized sterol synthesis in two sequenced Chlorella spp., the free-living C. sorokiniana, and symbiotic C. variabilis NC64A. Chlamydomonas reinhardtii was included as an internal control and Coccomyxa subellipsoidea as a plant-like outlier. We found that ergosterol was the major sterol produced by Chlorella spp. and C. reinhardtii, while C. subellipsoidea produced the three phytosterols found in plants. In silico analysis …

Correction: Moxley, R.A., Et Al. Intimate Attachment Of Escherichia Coli O157:H7 To Urinary Bladder Epithelium In The Gnotobiotic Piglet Model. Microorganisms 2020, 8, 263, Rodney A. Moxley, Tom W. Bargar, Stephen D. Kachman, Diane R. Baker, David Francis

School of Veterinary and Biomedical Sciences: Faculty Publications

The authors wish to make the following corrections to this paper [1]: On page 2, the sentence that reads, “Hence, EHEC is a rare but established cause of HUS in children and adults.” should read, “Hence, EHEC is a rare but established cause of UTI-associated HUS in children and adults.” On page 4, the sentence that reads, “As noted previously, 14 of 126 (13.3%) piglets orally inoculated with EHEC O157:H7 strains developed mild to moderate purulent cystitis within 8 d PI [25] (Table 1).” should read, “As noted previously, 14 of 105 (13.3%) piglets orally inoculated with EHEC O157:H7 strains …

Sestrins: Emerging Dynamic Stress-Sensors In Metabolic And Environmental Health, Seung Hyun Ro, Julianne Fay, Cesar I. Cyuzuzo, Yura Jang, Naeun Lee, Hyun Seob Song, Edward N. Harris

Department of Biochemistry: Faculty Publications

Proper timely management of various external and internal stresses is critical for metabolic and redox homeostasis in mammals. In particular, dysregulation of mechanistic target of rapamycin complex (mTORC) triggered from metabolic stress and accumulation of reactive oxygen species (ROS) generated from environmental and genotoxic stress are well-known culprits leading to chronic metabolic disease conditions in humans. Sestrins are one of the metabolic and environmental stress-responsive groups of proteins, which solely have the ability to regulate both mTORC activity and ROS levels in cells, tissues and organs. While Sestrins are originally reported as one of several p53 target genes, recent studies …

The Role Of Liver Sinusoidal Endothelial Cells In Liver Malady Homeostasis, Fatima Cabral

Department of Biochemistry: Dissertations, Theses, and Student Research

Current literature described techniques for the purification of liver cell types through text alone. The techniques described for the isolation of liver sinusoidal endothelial cells as well as hepatocytes described here are modified from a published article in the Journal of Visualized experiments. The video protocol allows for the user to successfully isolate cells as the most difficult parts of the procedure are demonstrated visually. The detection of liver maladies such as the non-alcoholic fatty liver disease, the stage if this disease and differentiation between non-alcoholic and alcoholic fatty liver disease is demonstrated in the development of a unique panel …

Editorial: Structure And Function Of Chloroplasts - Volume Ii, Yan Lu, Lu Ning Liu, Rebecca L. Roston, Jurgen Soll, Hongbo Gao

Department of Biochemistry: Faculty Publications

No abstract provided.

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 C. 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) biosynthesis …

Dissecting The Regulatory Network Of Sphingolipid Biosynthesis In Plants, Ariadna Gonzalez-Solis

Department of Biochemistry: Dissertations, Theses, and Student Research

Sphingolipids are a diverse group of lipids recognized as important components of cellular membranes and regulators of processes during development and in response to environmental stresses. Serine palmitoyltransferase (SPT) catalyzes the first step in sphingolipid biosynthesis and is a primary regulatory point for homeostasis. ORM proteins have been identified as negative regulators of SPT activity, however the mechanistic details of the regulation are only beginning to be understood. In this work, we show that ORM1 and ORM2 are essential for life cycle completion in Arabidopsis thaliana. Furthermore, the study of a structural ORM1 variant provided information about a transmembrane …

Curie Temperature Engineering In A Novel 2d Analog Of Iron Ore (Hematene) Via Strain, Renu Singla, Timothy A. Hackett, Sarvesh Kumar, Jyotsna Sharma, Manish K. Kashyap

Department of Biochemistry: Faculty Publications

As a newly exfoliated magnetic 2D material from hematite, hematene is the most far-reaching ultrathin magnetic indirect bandgap semiconductor. We have carried out a detailed structural analysis of hematene via prefacing strain by means of first-principles calculations based on density functional theory (DFT). Hematene in the pristine form emerges out to be a magnetic semiconductor with a bandgap of 1.0/2.0 eV for the majority/minority spin channel. The dependence of magnetic anisotropy energy (MAE), T_C, and the bandgap on compressive and tensile strains has been scanned exclusively. It is examined that T_C depends firmly on the compressive strain …

Changes In Lipid Profiles Of Epileptic Mouse Mode, Alicia Johnson, Ryan A. Grove, Deepak Madhavan, Cory H.T. Boone, Camila Pereira Braga, Hannah Kyllo, Kaeli K. Samson, Kristina A. Simeone, Timothy A. Simeone, Tomáš Helikar, Corrine K. Hanson, Jiri Adamec

Department of Biochemistry: Faculty Publications

Introduction Approximately 1% of the world’s population is impacted by epilepsy, a chronic neurological disorder characterized by seizures. One-third of epileptic patients are resistant to AEDs, or have medically refractory epilepsy (MRE). One non-invasive treatment that exists for MRE includes the ketogenic diet (KD), a high-fat, low-carbohydrate diet. Despite the KD’s success in seizure attenuation, it has a few risks and its mechanisms remain poorly understood. The KD has been shown to improve metabolism and mitochondrial function in epileptic phenotypes. Potassium channels have implications in epileptic conditions as they have dual roles as metabolic sensors and control neuronal excitation.

Objectives …

A Practical Guide To Mechanistic Systems Modeling In Biology Using A Logic-Based Approach, Anna Niarakis, Tomáš Helikar

Department of Biochemistry: Faculty Publications

Mechanistic computational models enable the study of regulatory mechanisms implicated in various biological processes. These models provide a means to analyze the dynamics of the systems they describe, and to study and interrogate their properties, and provide insights about the emerging behavior of the system in the presence of single or combined perturbations. Aimed at those who are new to computational modeling, we present here a practical hands-on protocol breaking down the process of mechanistic modeling of biological systems in a succession of precise steps. The protocol provides a framework that includes defining the model scope, choosing validation criteria, selecting …

Cautionary Tale Of Using Tris(Alkyl)Phosphine Reducing Agents With Nad+-Dependent Enzymes, Sagar M. Patel, Thomas G. Smith, Martha Morton, Kyle M. Stiers, Javier Seravalli, Stephen J. Mayclin, Thomas E. Edwards, John J. Tanner, Donald F. Becker

Department of Biochemistry: Faculty Publications

Protein biochemistry protocols typically include disulfide bond reducing agents to guard against unwanted thiol oxidation and protein aggregation. Commonly used disulfide bond reducing agents include dithiothreitol, β-mercaptoethanol, glutathione, and the tris(alkyl)phosphine compounds tris(2-carboxyethyl)phosphine (TCEP) and tris(3-hydroxypropyl)phosphine (THPP). While studying the catalytic activity of the NAD(P)H-dependent enzyme Δ¹-pyrroline-5-carboxylate reductase, we unexpectedly observed a rapid non-enzymatic chemical reaction between NAD⁺ and the reducing agents TCEP and THPP. The product of the reaction exhibits a maximum ultraviolet absorbance peak at 334 nm and forms with an apparent association rate constant of 231–491 M⁻¹ s⁻¹. The reaction is …

Characterization Of Human Pyrroline-5-Carboxylate Reductase Enzymes Responsible For L-Proline Biosynthesis, Sagar Patel

Department of Biochemistry: Dissertations, Theses, and Student Research

Pyrroline-5-carboxylate reductases (EC 1.5.1.2) are important housekeeping enzymes of L-proline biosynthesis, which generate L-proline and influence redox cycling of NAD(P)H/NAD(P)⁺ to support cellular growth in all domains of life. Structural evidence from X-ray crystal structures of HsPYCR1 (PDB codes 5UAT, 5UAU, and 5UAV) shows both NADPH bound in the N-terminal Rao-Rossmann fold motif and an important hydrogen bond or proton donor role for Thr238 with L-P5C. The Thr238Ala mutation results in 10-fold loss in catalytic efficiency with varied L-P5C relative to the wild-type enzyme, thus indicating Thr238’s potential hydrogen bond and proton donation to L-P5C is critical for catalysis. …

Protease Oma1 Modulates Mitochondrial Bioenergetics And Ultrastructure Through Dynamic Association With Micos Complex, Martonio P. Viana

Department of Biochemistry: Dissertations, Theses, and Student Research

Remodeling of mitochondrial ultrastructure is a complex dynamic process that is critical for a variety of mitochondrial functions and apoptosis. Although the key regulators of this process - mitochondrial contact site and cristae junction organizing system (MICOS) and GTPase Optic Atrophy 1 (OPA1) have been characterized, the mechanisms behind this regulation remain incompletely defined. Here, we found that in addition to its role in mitochondrial division, metallopeptidase OMA1 is required for maintenance of contacts between the inner and outer membranes through a dynamic association with MICOS. This association is independent of OPA1, appears to be mediated via the MIC60 MICOS …

Role Of The Hyaluronan Receptor, Stabilin-2/Hare, In Health And Disease, Edward N. Harris, Erika Baker

Department of Biochemistry: Faculty Publications

Stabilin-2/HARE is the primary clearance receptor for circulating hyaluronan (HA), a polysaccharide found in the extracellular matrix (ECM) of metazoans. HA has many biological functions including joint lubrication, ocular turgor pressure, skin elasticity and hydration, cell motility, and intercellular signaling, among many others. The regulatory system for HA content in the tissues, lymphatics, and circulatory systems is due, in part, to Stabilin-2/HARE. The activity of this receptor was discovered about 40 years ago (early 1980s), cloned in the mid-1990s, and has been characterized since then. Here, we discuss the overall domain organization of this receptor and how it correlates to …

Integrated Unicellular/Filamentous Algal Production, Harvesting And Remediation System, Paul N. Black, James Allen, Timothy J Nicodemus

Department of Biochemistry: Faculty Publications

A method of removing nitrogen-bound nitrate from at least one of groundwater, surface water, or waste water is disclosed. The method includes providing contaminant-containing water from groundwater, surface water, and/or waste water sources. The method further includes adding the contaminant-containing water to an algal photobioreactor system. The method further includes adding an alga culture to the alga photobioreactor system. The method further includes adjusting temperature, CO2 concentration, pH, light wavelength, and/or light intensity in the algal photobioreactor system to optimize the growth of the algea. The method further includes separating the aglae from the water and harvesting algal biomass.

Mutagenesis Of Claudins To Probe In Vivo Interactions And Assemblies, Currey Zalman, Alex J. Vecchio

UCARE: Research Products

Paracellular transport of solutes and the control of the flow of molecules through the intracellular space in vertebrate epithelia is directed by tight junctions (TJs). Claudins form paracellular barriers and pores that determine tight junction permeability. This investigation attempts to explain the molecular bases for destruction and reconstruction of tight junctions within epithelial cells, occurring via both natural and disease-causing mechanisms. This interdisciplinary research is important in the advancement of our understanding of human biology and health, as different disruptions to epithelial tight junctions are hallmarks of many human diseases. The overall objective was to take previously made Claudin containing …

The Role Of Conformational Dynamics In Isocyanide Hydratase Catalysis, Medhanjali Dasgupta

Department of Biochemistry: Dissertations, Theses, and Student Research

Post-translational modification of cysteine residues can regulate protein function and is essential for catalysis by cysteine-dependent enzymes. Covalent modifications neutralize charge on the reactive cysteine thiolate anion and thus alter the active site electrostatic environment. Although a vast number of enzymes rely on cysteine modification for function, precisely how altered structural and electrostatic states of cysteine affect protein dynamics, which in turn, affects catalysis, remains poorly understood.

Here we use X-ray crystallography, computer simulations, site directed mutagenesis and enzyme kinetics to characterize how covalent modification of the active site cysteine residue in the enzyme, isocyanide hydratase (ICH), affects the protein …

Clostridium Perfringens Adhesion Through Type Iv Pili, Alexander Meyer, Josephine Liess, Kurt Piepenbrink

UCARE: Research Products

Bacteria infect host cells through several mechanisms, one of which is a surface protein called a type IV pilus. Type IV pili are thin, hair-like protein fibers on the bacterial surface capable of being extended and retracted from a bacterial cell; they are used for functions including motility, biofilm formation, and adherence to host cells. Clostridium perfringens is a Gram-positive bacterium best known as a food pathogen that is believed to use type IV pili for host cell adherence. These pili are poorly characterized and understanding how C. perfringens uses type IV pili will provide a model for how these …

Characterization Of A Split-Nluc Assay For Monitoring Changes In Alpha-Synuclein Solubility In Living Cells, Baolong Truong

Honors Program: Senior Projects (Public)

Alpha-synuclein is the primary constituent of Lewy Bodies, protein aggregates associated with Parkinson’s Disease, Dementia with Lewy Bodies, and Multiple Systems Dystrophy. Given the terminal nature of these synucleinopathies, the need for an assay that can report on alpha-synuclein aggregation levels in living systems is critical. Western blotting represents one potential approach to this problem; however, this technique can often be limited by selectivity of available antibodies and experimental reproducibility. Herein, we describe a novel luminescence-based assay capable of detecting alpha-synuclein solubility in bacterial cells. This platform can report on the influence of disease-relevant mutations and small molecules. Antibodies are …

Structure, Function And Metabolism Of Hepatic And Adipose Tissue Lipid Droplets: Implications In Alcoholic Liver Disease, Sathish Kumar Natarajan, Karuna Rasineni, Murali Ganesan, Dan Feng, Benita L. Mcvicker, Mark A. Mcniven, Natalia A. Osna, Justin L. Mott, Carol A. Casey, Kusum K. Kharbanda

School of Veterinary and Biomedical Sciences: Faculty Publications

For more than 30 years, lipid droplets (LDs) were considered as an inert bag of lipid for storage of energy-rich fat molecules. Following a paradigm shift almost a decade ago, LDs are presently considered an active subcellular organelle especially designed for assembling, storing and subsequently supplying lipids for generating energy and membrane synthesis (and in the case of hepatocytes for VLDL secretion). LDs also play a central role in many other cellular functions such as viral assembly and protein degradation. Here, we have explored the structural and functional changes that occur in hepatic and adipose tissue LDs following chronic ethanol …

Fungicide Sensitivity Of Sclerotinia Sclerotiorum Isolates Selected From Five Different States That Use Different Fungicide Treatments, Cristian Wulkop Gil

UCARE: Research Products

Sclerotinia sclerotiorum is a plant pathogenic fungus that causes a disease called white mold that can infect more than 450 plant species including soybeans, dry beans, green beans, canola, and sunflower. This pathogen is capable of up to $252M in losses every year (U.S. Canola Association, 2014). Fungicides are widely used in developed agricultural systems to control disease. However, resistance to the most effective fungicides has emerged and spread in pathogen populations and there have been multiple reports of S. sclerotiorum isolates becoming resistant to certain fungicides. Since different fields in different states use different fungicide treatments on plants and …

Got Science? Club, Nora Husein, Randa Ismail

Honors Program: Expanded Learning Clubs

Got Science? Club allows students to learn about the science that can be found in our daily lives using everyday items such as food and school supplies. Students will learn about these sciences through hands-on experiments, allowing them to truly experience the science around them.

Periodic Table Club, Makayla Gill, Kailynn Jensen

Honors Program: Expanded Learning Clubs

This club is dedicated to teaching the generation of future scientists the periodic table. This is designed to be a unique take on a STEM club that uses the periodic table as a backbone for a solid foundation in chemistry.

Dgts Production As A Phosphate Starvation Response In The Human Fungal Pathogen Candida Albicans, Caleb J. Wehling

School of Biological Sciences: Dissertations, Theses, and Student Research

Betaine lipids are a class of membrane lipids with betaine head groups. Three betaine lipids are known: diacylglyceryltrimethylhomoserine (DGTS), diacylglycerylhydroxymethylalanine (DGTA), and diacylglycerylcarboxymethylcholine (DGCC). Betaine lipids are most common in algae, although DGTS, the most common betaine lipid, is also found in many bacteria and fungi. Organisms which produce betaine lipids (especially DGTS) often don’t produce phosphatidylcholine (PtdCho), and DGTS structure resembles PtdCho structure without any phosphorous, leading to the hypothesis that betaine lipids may substitute for phospholipids in some organisms. This has been confirmed by discoveries that some organisms are capable of switching their membrane composition from PtdCho to …

Membrane Lipid Extraction Methods From Sorghum Bicolor, Max Regester

Honors Program: Senior Projects (Public)

Plants are the basis of the world as we know it. As sessile beings, there are often subject to many environment stressors like drought, extreme temperatures, etc. One way of analyzing how plants respond to these stressors is by monitoring changes in their lipid compositions. Having a better understanding of how plants respond to different stressors can have very important implications when it comes to cultivating crops. When testing lipid composition, it is important to measure levels as they were in the living tissue. The problem is, enzymes known as lipases are active during extraction and can greatly change the …

Development And Implementation Of A Biochemistry Argumentation Task To Promote Scientific Literacy Among Undergraduate Students, Lukas Hall

Honors Program: Senior Projects (Public)

Science education reform efforts at the postsecondary level have been lacking regardless of meaningful reform at the K-12 level. Of these reforms, the Next Generation Science Standards (NGSS) serve to reframe effective science teaching and learning as three-dimensional (3D). That is, 3D instruction integrates core disciplinary ideas, cross-cutting concepts, and science practices to support students’ science learning. There have been calls to extend this 3D model to the postsecondary level. The purpose of this study was to design, implement, and evaluate a 3D task in a university-level biochemistry course. The task was implemented as a homework assignment to 107 students …

Transcriptome Analysis-Identified Long Noncoding Rna Crnde In Maintaining Endothelial Cell Proliferation, Migration, And Tube Formation, Matthew Moran, Xiao Cheng Zeng, Mohamed Sham Shihabudeen Haider Ali, Nishikant Wase, Nghi Nguyen, Weilong Yang, Chi Zhang, Concetta C. Dirusso, Xinghui Sun

Department of Biochemistry: Faculty Publications

Obesity is a leading risk factor for type-2 diabetes. Diabetes often leads to the dysregulation of angiogenesis, although the mechanism is not fully understood. Previously, long noncoding RNAs (lncRNAs) have been found to modulate angiogenesis. In this study, we asked how the expression levels of lncRNAs change in endothelial cells in response to excessive palmitic acid treatment, an obesitylike condition. Bioinformatics analysis revealed that 305 protein-coding transcripts were upregulated and 70 were downregulated, while 64 lncRNAs were upregulated and 46 were downregulated. Gene ontology and pathway analysis identified endoplasmic reticulum stress, HIF-1 signaling, and Toll-like receptor signaling as enriched after …

Compounds For Increasing Lipid Synthesis And Storage, Concetta C. Dirusso, Nishikant Wase

Department of Biochemistry: Faculty Publications

This invention relates to methods for increasing lipid production in cells. Methods of producing biofuel from cells and preparing mutraceuticals comprising lipids produced according to a method provided herein are also provided.

Differentiation Of Mannheimia Haemolytica Genotype 1 And 2 Strains By Visible Phenotypic Characteristics On Solid Media, Emily L. Wynn, Gennie Schuller, John D. Loy, Aspen M. Workman, T. G. Mcdaneld, Michael L. Clawson

School of Veterinary and Biomedical Sciences: Faculty Publications

Genotype 2 Mannheimia haemolytica associate with the lungs of cattle with bovine respiratory disease more frequently than genotype 1 strains. Different colony colors and morphologies were identified between genotype 1 and 2 solid media cultures. Genotype of strains, and frequency differences between them in mixed cultures are discernable by visual inspection.

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Biotech Connector Brochure

Biotech Connector

The Biotech Connector represents an important opportunity to serve the economic needs of the people of Nebraska through further diversification of Nebraska's economy, and by helping forge and illuminate a pathway to jobs in the biotechnology space for Nebraska students.

The Biotech Connector is 7,700 sq. ft. of well-equipped wet-lab space located on Nebraska Innovation Campus. We provide incubation space and services to bioscience startups and high-growth biotech and research-based businesses.

Wet lab space provides aspiring startups and technology businesses with access to very expensive laboratory equipment that would be outside of the budget of most startups. Lack of access …