Biochemistry, Biophysics, and Structural Biology Commons^™

The Differences Between Iron And Iron-Substituted Manganese Superoxide Dismutase With Respect To Hydrogen Peroxide Treatment, Jianing Wang

Theses and Dissertations--Chemistry

Iron-substituted manganese superoxide dismutase (Fe(Mn)SOD) was produced using an in vivo preparation method. It’s an inactive enzyme in catalyzing superoxide radical dismutation owing to the mis-incorporation of Fe in the active site evolved to use Mn. To investigate the possible toxicity of human Fe(Mn)SOD proposed by Yamakura, we studied the properties of Fe(Mn)SOD upon H₂O₂ treatment and compared to that of FeSOD. It’s found that the responses to H₂O₂ treatment were different, including the changes of optical spectra, variations of active site coordination and secondary structures. Fe³⁺ reduction was not observed in Fe(Mn)SOD …

Bioc 435: Advanced Topics In Biochemistry—A Peer Review Of Teaching Project Benchmark Portfolio, Edward N. Harris

UNL Faculty Course Portfolios

BIOC 435 or Advanced Topics in Biochemistry is an ACE 10 (Achievement centered education)course for students in their senior year. This is a capstone course for Biochemistry majors and is the last of several biochemistry courses that they will take in their undergraduate enrollment. The course is also open to non-majors in a related science such as Biology and Biological Sciences, although these students typically do not do as well as the majors. Students who take this course should be well-prepared in the basic concepts of biochemistry with regards to nucleic acids and proteins as well as some familiarity with …

High Fat Diet Increased Serum Glutamate Dehydrogenase More Than Chronic Acetaminophen Dosing In Female Mice, Elizabeth Ruth Behmer

All Graduate Theses, Dissertations, and Other Capstone Projects

This laboratory study examined the effects of acetaminophen overdose in normal fed and high-fat fed female mice. Forty female mice were placed on normal and high-fat diets at 4 weeks old. When the mice were significantly different in weight (between 6 and 9 months old), half the mice were dosed with acetaminophen. These mice were daily given an overdose of acetaminophen for 14 days. The dose used was 300 mg/kg mouse (LD50 = 338 mg/kg). The control group was given 10 µl water/g mouse. Levels of serum glutamate dehydrogenase (GDH) were measured to indicate liver damage. GDH is released from …

Modulation Of Cholera Toxin Structure And Function By Host Proteins, Helen Burress

Electronic Theses and Dissertations

Cholera toxin (CT) moves from the cell surface to the endoplasmic reticulum (ER) where the catalytic CTA1 subunit separates from the holotoxin and unfolds due to its intrinsic thermal instability. Unfolded CTA1 then moves through an ER translocon pore to reach its cytosolic target. Due to the instability of CTA1, it must be actively refolded in the cytosol to achieve the proper conformation for modification of its G protein target. The cytosolic heat shock protein Hsp90 is involved with the ER-to-cytosol translocation of CTA1, yet the mechanistic role of Hsp90 in CTA1 translocation remains unknown. Potential post-translocation roles for Hsp90 …

The Burden Of Avian Influenza Viruses In Community Ponds In California, Zin Htway

Walden Dissertations and Doctoral Studies

Emerging influenza viruses continue to challenge public health. The problem is public health science professionals have been battling emerging human influenza diseases with tactile and reactionary methods because there is a lack of knowledge and data at the human-animal interface. This research was a baseline study of the proportion of influenza A virus (IAV) in urban and rural communities in California. The population was artificial recirculating water ponds in the geographic locations of rural and urban Californian communities. Surface water samples [N = 182] were collected from artificial recirculating ponds in California. Positivity for IAV was verified by real time …

Dimethylarginine Dimethylaminohydrolase Ii Overexpression Attenuates Lps-Mediated Lung Leak In Acute Lung Injury, Saurabh Aggarwal, Christine M. Gross, Sanjiv Kumar, Christiana Dimitropoulou, Shruti Sharma, Boris A. Gorshkov, Supriya Sridhar, Qing Lu, Natalia V. Bogatcheva, Agnieszka J. Jezierska-Drutel, Rudolf Lucas, John D. Catravas, Stephen M. Black

Bioelectrics Publications

Acute lung injury (ALI) is a severe hypoxemic respiratory insufficiency associated with lung leak, diffuse alveolar damage, inflammation, and loss of lung function. Decreased dimethylaminohydrolase (DDAH) activity and increases in asymmetric dimethylarginine (ADMA), together with exaggerated oxidative/nitrative stress, contributes to the development of ALI in mice exposed to LPS. Whether restoring DDAH function and suppressing ADMA levels can effectively ameliorate vascular hyperpermeability and lung injury in ALI is unknown, and was the focus of this study. In human lung microvascular endothelial cells, DDAH II overexpression prevented the LPS-dependent increase in ADMA, superoxide, peroxynitrite, and protein nitration. DDAH II also attenuated …

Methanol And Ethanol Modulate Responses To Danger- And Microbe- Associated Molecular Patterns In Tomato, Tobacco And Arabidopsis, Claire Teresa Hann

Theses and Dissertations

Methanol is a byproduct of cell wall modification. It is released through the action of pectin methylesterases (PMEs), which demethylate cell wall pectins. Plant PMEs play not only a role in developmental processes but also in responses to herbivory and infection by fungal or microbial pathogens, resulting in increased methanol release. To break down the cell wall barrier, pathogens employ their own PMEs. Interestingly, the infection process also regulates the expression of certain plant PMEs. Methanol is toxic to a number of herbivores and reduces their fitness. At high concentrations, it upregulates signaling and defense genes. However, molecular mechanisms that …

Mitochondrial Replication From Embryogenesis To Early Adulthood, In Dui Species, Mytilus Galloprovincialis, Ellen Blenn Richardson

Theses and Dissertations

Eukaryotes typically inherit mitochondria strictly maternally. There are however a group of bivalve molluscs that inherit different mitochondrial genomes from each parent. The paternally inherited mtDNA (M-type) is localized to, and dominates over the maternally inherited mtDNA (F-type) in the gonads of the male offspring, but is not normally retained in any tissue of the female offspring. This process is termed Double Uniparental Inheritance (DUI). Using quantitative PCR (qPCR), this study examines mtDNA replication compared to total DNA replication through embryonic stages of development and into early adulthood of the DUI species, Mytilus galloprovincialis. Results indicate that up through the …

Catalytic Mechanism And Maturation Of The Metalloenzyme Nitrile Hydratase, Natalie I. Gumataotao

Dissertations

Nitrile hydratases are metalloenzymes that catalyze the hydration of nitriles to their corresponding amides in a specific manner at ambient pressures and temperatures at neutral pH. Traditional industrial methods require high temperature and pressure, extreme pH, and heavy metals. NHases are used as biocatalysts in the large scale industrial production of amide precursors to textiles, animal feedstock, and polymers. Notably, NHase is used in the production of ~100,000 tons of acrylamide annually by the Mitsubishi Corporation.

Despite being used extensively in industry, questions remain about NHase. The catalytic mechanism is not defined. Understanding the way in which the nitrile is …

Investigating The Role Of The Pgf2 Alpha/Calcineurin-Signaling Pathway In The Regulation Of Adipogenesis, Damodaran Annamalai

Dissertations

Prostaglandin F2α (PGF2α) is a potent physiological inhibitor of adipocyte differentiation. In previous studies, we demonstrated that PGF2α inhibits adipogenesis via activation of the calcium-regulated protein phosphatase, calcineurin. In this current study, we have now extended these findings to identify the IL-11 cytokine and the Nurr1 orphan nuclear hormone receptor as functionally important downstream transcriptional targets of the PGF2α/calcineurin-pathway involved in the inhibition of adipocyte differentiation. In the case of IL-11, we show that this cytokine acts in an autocrine fashion to inhibit adipogenesis via the essential actions of the gp130 cytokine co-receptor signaling subunit. Further, by using a well-characterized …

Genetic Stock Identification And Migration In Black Sea Bass (Centropristis Striata) Along The Western Atlantic Coast And Gulf Of Mexico, Justin Francis Lewandowski

Theses and Dissertations

The black sea bass, Centropristis striata, is a member of the family Serranidae that is commercially important throughout its range, which extends throughout the western Atlantic (from Cape Cod, Massachusetts to Cape Canaveral, Florida) and Gulf of Mexico (from Mobile Bay, Alabama to Tampa Bay, Florida). There are two known subspecies, C. striata striata in the Atlantic and C. striata melana in the Gulf, and through behavioral and morphological evidence two separate stocks are managed in the Atlantic, north and south of Cape Hatteras, NC. Recent genetic studies on mitochondrial DNA (mtDNA) have supported this. To further investigate the relationships …

Numerical Study Of Lipid Translocation Driven By Nanoporation Due To Multiple High-Intensity, Ultrashort Electrical Pulses, Viswanadham Sridhara, Ravindra P. Joshi

Electrical & Computer Engineering Faculty Publications

The dynamical translocation of lipids from one leaflet to another due to membrane permeabilization driven by nanosecond, high-intensity (>100 kV/cm) electrical pulses has been probed. Our simulations show that lipid molecules can translocate by diffusion through water-filled nanopores which form following high voltage application. Our focus is on multiple pulsing, and such simulations are relevant to gauge the time duration over which nanopores might remain open, and facilitate continued lipid translocations and membrane transport. Our results are indicative of a N^1/2 scaling with pulse number for the pore radius. These results bode well for the use of pulse …

Mutations In Phospholamban Alter The Structure And Function Of The Calcium Atpase Regulatory Complex, Neha Abrol

Dissertations

Phospholamban (PLB) is an integral membrane protein that plays an important role in regulation of cardiac calcium handling and contractility. PLB exists as a homopentamer in the membrane, which upon deoligomerization into active monomers reversibly inhibits sarco/endoplasmic reticulum calcium ATPase (SERCA). Mutations in PLB that change the PLB monomer-pentamer equilibrium result in dysregulation of SERCA. To determine the structural and regulatory role of the C-terminal residues of PLB in the membranes of living cells, we fused fluorescent protein tags to PLB and SERCA. We then studied the effect of C-terminal alanine substitutions and truncation mutations on PLB oligomerization and SERCA …

The Dape-Encoded N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase (Dape) From Haemophilus Influenzae As A Prospective Target For The Development Of Novel Antibiotics, Anna Starus

Dissertations

The rapid emergence of bacteria that are resistant to todayfs antibiotics makes them more and more ineffective. Consequently, the need for a novel class of antibacterial agents is rapidly increasing. The importance of this project is emphasized by the emergence of several pathogenic bacterial strains that are resistant to all currently available antibiotics on the market today. One way to approach this problem is to develop drugs that target essential bacterial biosynthetic pathways. Based on bacterial genetic information, the meso]diaminopimelate (mDAP)/lysine biosynthetic pathway offers several potential anti]bacterial targets that have not been yet explored. One of these, the dapE-encoded N-succinyl-L,L-diaminopimelic …

Lineage-Specific Transcriptional Profiles Of Symbiodinium Spp. Unaltered By Heat Stress In A Coral Host, Daniel J. Barshis, Jason T. Ladner, Thomas A. Oliver, Stephen R. Palumbi

Biological Sciences Faculty Publications

Dinoflagellates of the genus Symbiodinium form an endosymbiosis with reef building corals, in which photosynthetically derived nutrients comprise the majority of the coral energy budget. An extraordinary amount of functional and genetic diversity is contained within the coral-associated Symbiodinium, with some phylotypes (i.e., genotypic groupings), conferring enhanced stress tolerance to host corals. Recent advances in DNA sequencing technologies have enabled transcriptome-wide profiling of the stress response of the cnidarian coral host; however, a comprehensive understanding of the molecular response to stress of coral-associated Symbiodinium, as well as differences among physiologically susceptible and tolerant types, remains largely unexplored. Here, …

Atm, Brca1, And Aurora A: Mechanisms Of G2/M Checkpoint Control In Human Embryonic Stem Cells, Jason Beckta

Theses and Dissertations

When cultured in vitro, human embryonic stem cells (hESCs) acquire genetic abnormalities that have slowed their therapeutic use. As hESCs have a “leaky” G1/S boundary, the pressure of ensuring genetic integrity falls on the G2/M checkpoint, which can be activated by failed chromosomal decatenation (among other stimuli). It is hypothesized that hESCs have a deficient decatenation checkpoint, but little data supports this. Evidence suggests that the ataxia telangiectasia mutated (ATM) kinase controls the G2/M decatenation and DNA damage checkpoints, though previous reports are conflicting on this point. My work demonstrates that inhibition of decatenation activates ATM and arrests hESCs in …

The Cytotoxic Effect Of The Bcl-2 Family Of Proteins In Breast Cancer Cells, Yamileth Chin

Theses and Dissertations

Breast cancer is the second leading cause of death amongst women ages 20 to 59. Despite advancements in cancer therapies, more research is necessary to improve the diagnoses and treatment of several types of breast cancer. Paclitaxel (Taxol) is a commonly utilized anti-cancer drug for various types of solid tumors. However, the molecular mechanism utilized by paclitaxel to induce cell death is still elusive. Previous studies in our laboratory have shown that the pro-apoptotic BCL-2 family protein, BAK (BCL-2 homologous antagonist/killer) plays an important role in paclitaxel-induced cell death. In untreated breast cancer cells, BAK is associated with the anti-apoptotic …

Folate Conjugated Dendrimers For Targeted Anticancer Therapy, Shannon Andrews

Theses and Dissertations

Anticancer therapeutics are often limited to suboptimal doses due to their lack of selectivity for tumor cells and resultant damage to healthy tissue. These limitations motivated researchers to develop tumor-specific delivery systems for improved therapeutic efficacy and reduced unintended cytotoxicity. Polyamidoamine dendrimers offer an ideal platform for designing targeted therapeutics with tunable characteristics that optimize pharmacokinetic behavior and targeting specificity. Ligand conjugation to dendrimer provides the biochemical interaction necessary to activate tumor-specific receptors for receptor-mediated endocytosis and effective internalization of polyplexes. Tumor-specific receptors overexpressed in carcinomas, like folate receptor-alpha (FOLRα), are targeted by ligand-conjugated dendrimer to allow enhanced internalization of …

Regulation Of Ykl-40 In Sterile Inflammation And Its Role In Glioblastoma In Vivo, Reetika Bhardwaj

Theses and Dissertations

YKL-40 is a secreted glycoprotein, which is a shared biomarker of chronic inflammation and oncogenic transformation. Indeed, YKL-40 expression is up-regulated in many diseases including multiple sclerosis, Alzheimer disease, viral encephalitis, HIV-associated dementia, brain infarction, and traumatic brain injury. YKL-40 is also expressed by several solid tumors, such as osteosarcoma, ovarian carcinoma and glioblastoma multiforme (GBM). It promotes the migration and invasion of astrocytes as well as GBM cells. Serum YKL-40 levels have been shown to directly correlate with tumor grade and potentially tumor burden in GBM. In contrast to the numerous reports documenting elevated expression of YKL-40, relatively little …

Developing A Caenorhabditis Elegans Model For Marfan Syndrome, Pauline Fotopoulos

Theses and Dissertations

Marfan Syndrome (MFS) is one of the most common monogenic diseases and affects approximately 1 in 5,000 individuals worldwide. The syndrome is characterized by elongated extremities, tall stature, slender frame, and cardiac, and vision abnormalities due to severe connective tissue defects. It is caused by mutations in the fbn1 gene, which encodes an extracellular matrix glycoprotein, and is required for proper cardiac and skeletal development and for sequestration of TGFβ (transforming growth factor beta) and BMP (bone morphogenetic protein) within the extracellular matrix (ECM). The primary objective of this study was to establish a C.elegans MFS model and use this …