Physical Sciences and Mathematics Commons^™

Substrate Binding And Reduction Mechanism Of Molybdenum Nitrogenase, Zhiyong Yang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As a key constituent of proteins, nucleic acids, and other biomolecules, nitrogen is essential to all living organisms including human beings. Dinitrogen represents the largest pool of nitrogen, about 79% of the Earth’s atmosphere, yet it is unusable by most living organisms due to its inertness. There are two ways to fix this inert dinitrogen to usable ammonia. One is the industrial Haber-Bosch process, which needs to be conducted at high temperature and pressure. This process uses a lot of the non-renewable fossil fuel as the energy source. The other major pathway is the biological nitrogen fixation carried out by …

Membrane Lipid-Modulated Mechanism Of Action And Non-Cytotoxicity Of Novel Fungicide Aminoglycoside Fg08, Sanjib Shrestha, Michelle Grilley, Marina Y. Fosso, Cheng-Wei Tom Chang, Jon Y. Takemoto

Chemistry and Biochemistry Faculty Publications

A novel aminoglycoside, FG08, that differs from kanamycin B only by a C8 alkyl chain at the 4″-O position, was previously reported. Unlike kanamycin B, FG08 shows broad-spectrum fungicidal but not anti-bacterial activities. To understand its specificity for fungi, the mechanism of action of FG08 was studied using intact cells of the yeast Saccharomyces cerevisiae and small unilamellar membrane vesicles. With exposure to FG08 (30 µg mL−1), 8-fold more cells were stained with fluorescein isothiocyanate, cells had 4 to 6-fold higher K+ efflux rates, and 18-fold more cells were stained with SYTOX Green in comparison to exposure to kanamycin B …

An Electrolysis Experiment For A Middle School Summer Science Camp, Mike A. Christiansen, Leslie Jessup, Kevin D. Woodward

Chemistry and Biochemistry Faculty Publications

Higher education is often culturally deemphasized in the geographic area served by our rural, regional campus. As a result, faculty members have the opportunity to spearhead teaching efforts designed to educate the community about the importance of obtaining a post-secondary degree. To this end, we recently held a Science Summer Camp for middle school students, designed to infuse young people with an increased excitement for STEM (Science, Technology, Engineering, and Math) education. In this report, we summarize a chemical electrolysis experiment we carried out with middle school students for our annual Science Summer Camp. We also provided procedural guidelines for …

Oxidative Aliphatic Carbon-Carbon Bond Cleavage Reactions, Caleb J. Allpress

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The work presented in this dissertation has focused on the activation and cleavage of chemical bonds between two carbon atoms. The selective oxidative activation of carbon-carbon bonds is important due to potential applications in the utilization of biomass for fuel production, applications in wastewater treatment and bioremediation, and in developing new reactions for organic synthesis of fine chemicals including pharmaceuticals. Ideally these reactions would be carried out with high atom economy at low temperatures and pressures, and using earth-abundant elements as reagents and catalysts. With these points in mind, nature provides an ideal model framework, carrying out its chemistry at …

Enhanced Structural Support Of Metal Sites As Nodes In Metal-Organic Frameworks Compared To Metal Complexes, Sanjit Das

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Crystalline porous materials have gained long-standing interest for their application in gas storage, separation and catalysis. These materials have been useful for domestic, scientific and industrial purposes for many decades. Zeolites are a well known example of such materials.

Metal-organic frameworks are a new class of crystalline porous materials. They have many advantages over the more widely known zeolites. Though metal-organic frameworks are relatively new, their basic structure, known as the secondary building unit, very closely resembles the structure of metal complexes. Such metal complexes have been characterized in chemistry for more than a century.

Chemical catalysis is a process …

Structural And Functional Characterization Of The Ldp3 (Vhz) Protein Tyrosine Phosphatase, Vyacheslav I. Kuznetsov

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protein phosphorylation is as an important regulatory mechanism that controls a large number of physiologically important cellular processes. Proteins are phosphorylated on aliphatic (serine and threonine) as well aromatic (histidine and tyrosine) residues predominantly located on sterically accessible loops. Phosphorylation affects three- dimensional structures of proteins resulting in conformational changes which activate or deactivate enzymatic functions. Because of the ability of protein phosphorylation to modulate a multitude of diverse cellular processes, it became an appealing and promising target for drug therapy.

Attachment of phosphate is accomplished by kinases, whereas the removal of the phosphoryl group is performed by protein phosphatases. …

Mesobiliverdin Ixα Enhances Rat Pancreatic Islet Yield And Function, Taihei Ito, Dong Chen, Cheng-Wei Tom Chang, Takashi Kenmochi, Tomonori Saito, Satoshi Suzuki, Jon Y. Takemoto

Chemistry and Biochemistry Faculty Publications

The aims of this study were to produce mesobiliverdin IXα, an analog of anti-inflammatory biliverdin IXα, and to test its ability to enhance rat pancreatic islet yield for allograft transplantation into diabetic recipients. Mesobiliverdin IXα was synthesized from phycocyanobilin derived from cyanobacteria, and its identity and purity were analyzed by chromatographic and spectroscopic methods. Mesobiliverdin IXα was a substrate for human NADPH biliverdin reductase. Excised Lewis rat pancreata infused with mesobiliverdin IXα and biliverdin IXα-HCl (1–100 μM) yielded islet equivalents as high as 86.7 and 36.5%, respectively, above those from non-treated controls, and the islets showed a high degree of …

Characterization Of A Novel Fusion Protein Of Ipab And Ipad Of Shigella And Its Potential As A Pan-Shigella Vaccine, F. J. Martinez-Becerra, X. Chen, Nicholas E. Dickenson, S. P. Choudhari, K. Harrison, J. D. Clements, W. D. Picking, L. L. Van De Verg, R. I. Walker, W. L. Picking

Chemistry and Biochemistry Faculty Publications

Shigellosis is an important disease in the developing world, where about 90 million people become infected with Shigella spp. each year. We previously demonstrated that the type three secretion apparatus (T3SA) proteins IpaB and IpaD are protective antigens in the mouse lethal pulmonary model. In order to simplify vaccine formulation and process development, we have evaluated a vaccine design that incorporates both of these previously tested Shigella antigens into a single polypeptide chain. To determine if this fusion protein (DB fusion) retains the antigenic and protective capacities of IpaB and IpaD, we immunized mice with the DB fusion and compared …

The Magnitude And Mechanism Of Charge Enhancement Of Ch∙∙O H-Bonds, U. Adhikari, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Quantum calculations find that neutral methylamines and thioethers form complexes, with N-methylacetamide (NMA) as proton acceptor, with binding energies of 2–5 kcal/mol. This interaction is magnified by a factor of 4–9, bringing the binding energy up to as much as 20 kcal/mol, when a CH3+ group is added to the proton donor. Complexes prefer trifurcated arrangements, wherein three separate methyl groups donate a proton to the O acceptor. Binding energies lessen when the systems are immersed in solvents of increasing polarity, but the ionic complexes retain their favored status even in water. The binding energy is reduced when the methyl …