Physical Sciences and Mathematics Commons^™

Biochemical Characterization Of Four Distinct Proteins, Gustavo A. Avila

Open Access Theses & Dissertations

Proteins are ubiquitous in all living organisms, executing the majority of cellular functions in distinct ways. Understanding a protein's role necessitates investigating its structure and function, which are closely related. My research couples these two aspects by delving into the biochemical and structural characterization of proteins in four distinct systems, all playing central roles in numerous significant disease progressions. These four original research endeavors were all targeted for structural studies with a unifying relationship to establish our new structural biochemistry lab. These four systems are: (1) Gam1, an early adenovirus protein globally inhibiting host SUMOylation; (2) Anthrax toxin complexed with …

Environmental Assessment Of Used Motor Oil In The Ciudad Juarez-El Paso Area, Alma Leticia Figueroa

Open Access Theses & Dissertations

As a hazardous waste generated in large amounts worldwide, used motor oil (UMO) is an important issue for environmental science. UMO contains the carcinogenic and mutagenic compounds Polycyclic Aromatic Hydrocarbons (PAHs). Unless properly managed and disposed of PAHs remain in the environment, principally in sediments and soil. From such environmental sinks, PAHs can migrate to watersheds contaminate drinking water, and damage ecosystems and human health.

Generators of used oil include "businesses that handle used oil through commercial or industrial operations or from the maintenance of vehicles and equipment," (United States Environmental Protection Agency (USEPA), 2013). An example of such a …

Structural Investigation Of The Molecular Chaperonin Tf55 From Thermophilic Archaeon Sulfolobus Solfataricus, Sanjay Kumar Molugu

Open Access Theses & Dissertations

Chaperonins are ubiquitous multi-subunit macromolecules that mediate the folding and assembly of certain proteins that cannot fold properly in vivo. The Archaea bacterium Sulfolobus solfataricus encodes for three chaperonin complexes formed from three different, but closely related subunits named alpha,betaand Gamma. These subunits form a homo-18mer composed of all beta subunits at temperatures ranging between 80oC-85oC, a hetero-16mer composed of alpha and beta subunits at temperatures ranging between 70oC-75oC and a hetero 18mer composed of alpha, beta and gamma subunits at temperatures of 60oC. Structures exist for the chaperonin TF55 all-beta complex and for the TF55 alpha-beta complex but not …

Isomerase Activity Of Candida Rugosa Lipase In Conversion Of Racemic Ibuprofen To (S)-Ibuprofen, Saideh Sadat Mortazavi

Open Access Theses & Dissertations

The Candida rugosa lipase-catalyzed Dynamic Kinetic Resolution of racemic ibuprofen methyl ester was optimal at pH 7.6 to produce (S)-ibuprofen in 72 hours. The concentration of various buffers for these reactions ranged from 0.2 to 0.5 M. The commercial lipase was found to be acidic altering the final pH of the reaction mixtures. Dimethylformamide co-solvent maintained the reaction pH better than dimethylsulfoxide, with evidence of the latter functioning as an oxidizing agent. Lower concentrations of ibuprofen methyl ester and higher stirring rates led to faster conversions. The minimal amount of lipase needed was 20 mg/mL buffer. Reaction of (R)-ibuprofen methyl …

Design And Synthesis Of Porous Organic Frameworks For H2 And Ch4 Storage And For Selective Co2 Adsorption, Venkata Neti

Open Access Theses & Dissertations

Three new boronate-ester based covalent organic frameworks (CoPc-PorDBA, CoPc-BPDA and HHTP-PorDBA), an imine-linked porphyrin porous polymer (CuPor-BPDC) and imine and benzothiazole based porous polymers (IBTP), and a triazole based phthalocyanine "click" polymer (Pc-POP) were synthesized. The CoPc-PorDBA and CoPc-BPDA COFs exhibited high BET surface areas (1087, 1315 m2 g-1, respectively) whereas HHTP-PorDBA showed a low BET surface area of 205 m2 g-1. The H2 storage capacities of CoPc-BPDA and CoPc-PorDBA range between 0.8-1.2wt% at 77K, 1bar and the CH4 storage capacities range between 0.4-0.8wt% at 298K, 1bar. These materials also had good thermal stabilities up to 350° C. The BET …

Determination Of The Uptake And Effects Of Tio2 Nanoparticles In Cucumber (Cucumis Sativus), Alia D. Servin

Open Access Theses & Dissertations

The profuse use of nanoparticles (NPs) in consumer products has raised concerns about their impacts in environmental and human health and possible transfer into the food chain through plants. Cucumber (Cucumis sativus L.) is a widely cultivated garden vegetable that could be in contact with NPs through biosolids. In this Dissertation research, the impact of TiO2 NPs was evaluated in cucumber plants grown in hydroponics and sandy loam soil. Hydroponically grown plants were treated for 15 days with 0-4000 mg/L of TiO2 NPs, and their vegetative tissues were studied using synchrotron micro X-Ray Fluorescence (micro-XRF) and Micro X-ray Absorption Near …

Alkali Promoted Molybdenum (Iv) Sulfide Based Catalysts, Development And Characterization For Alcohol Synthesis From Carbon Monoxide And Hydrogen, Belinda Delilah Molina

Open Access Theses & Dissertations

For more than a century transition metal sulfides (TMS) have been the anchor of hydro-processing fuels and upgrading bitumen and coal in refineries worldwide. As oil supplies dwindle and environmental laws become more stringent, there is a greater need for cleaner alternative fuels and/or synthetic fuels. The depletion of oil reserves and a rapidly increasing energy demand worldwide, together with the interest to reduce dependence on foreign oil makes alcohol production for fuels and chemicals via the Fischer Tropsch synthesis (FTS) very attractive. The original Fischer-Tropsch (FT) reaction is the heart of all gas-to-liquid technologies; it creates higher alcohols and …

Effects Of Cerium Oxide Nanoparticles In Cereals: Insights Into The Toxicity Mechanisms And Macromolecular Modifications, Cyren Mendoza Rico

Open Access Theses & Dissertations

Despite the inundation of studies on the interaction of engineered nanomaterials (ENMs) with plants, investigations involving complete life cycle (i.e from seedling establishment to full maturity) are still lacking. Assessments on the nutritional value of plants cultivated to full maturity in ENMs-treated soil are also missing. Cerium oxide nanoparticles (nCeO2) have significant interactions with plants; however, there are no life cycle studies yet on their implications in cereals like rice (Oryza sativa L.), wheat (Triticum aestivum L.), and barley (Hordeum vulgare L.). These cereals are globally important crops that support the economic activity, and nutritional and health needs of billions …

Synthesis And Characterization Of Platinum(Ii) Complexes Of Electron Donor And Acceptor Ligands, Namrata Khanal

Open Access Theses & Dissertations

Pt(II) complexes of N,N-diphenylpyridineamine or 4-diphenylphosphino derivatized triphenylamine as novel electron donors and alkynyl derivatized benzothiadiazole as electron acceptors were synthesized. All the complexes were characterized by 1H and 13C nuclear magnetic resonance spectroscopy, electronspray ionization mass spectrometry, infrared spectroscopy, and 31P nuclear magnetic resonance spectroscopy for the complexes of 4-diphenylphosphino derivatives. The electronic properties studied using UV/vis spectroscopy exhibit ᴫ-ᴫ* transition, metal to ligand charge transfer, and optical highest occupied molecular orbital-lowest unoccupied molecular orbital bandgaps from 2.62-2.65 eV. The electrochemical study performed using cyclic voltammetry have shown the highest occupied molecular orbital-lowest unoccupied molecular orbital bandgaps from 2.70-2.74 …

Synthesis Of Peptide-Α-Phenylthioesters Using A Solid Support With A Photoreactive Nitroindoline Moiety, Andrew Pardo

Open Access Theses & Dissertations

Peptide-alpha-phenylthioesters are particularly reactive starting materials for Native Chemical Ligation. Here we present a new photochemical method for the synThesis of peptide-alpha-phenylthioesters under neutral reaction conditions with various C-terminal amino acids. The peptides were synthesized by Fmoc strategy on Sieber amide resin with a photoreactive nitroindoline linker. After cleavage of the photoreactive and fully protected peptide from the beads with dilute trifluoroacetic acid an auxiliary nucleophile such as N-hydroxybenzotriazole or N-hydroxysuccinimide is used to photochemically generate the activated peptide ester in situ. Then thiophenol is introduced in the dark. This new method enabled us to synthesize peptide-alpha-phenylthioesters up to 21 …

Synthesis And Characterization Of Fluorophores For The Detection Of Lanthanides And Actinides, Robinson I. Roacho

Open Access Theses & Dissertations

A series of fluorophores based in the boron dipyrromethene (BODIPY) family were synthesized and characterized. These fluorophores have the capacity of being introduced to a carbamoyl methyl phosphine oxide (CMPO) lanthanide/actinide extractant. These blue, green and red emission fluorophores show high thermal/moisture stability and high fluorescence efficiencies. The fluorescence intensity seems to be dependent on the restricted rotation about the C(8)-C bond in 8-Ph-BODIPY. By taking advantage of this feature, a hydroxyl- containing BODIPY with high fluorescence intensity was synthesized to be incorporated to a CMPO carboxylic acid via esterification. Unfortunately, we did not observe an optical response upon the …

Application Of Stir Bar Sorptive Extraction Thermal Desorption Gas Chromatography Mass Spectrometry For The Study Of Water Accommodated Fractions Of Fossil Fuels And Biodiesel, Ricardo Mccreary

Open Access Theses & Dissertations

Even though measures are taken to decrease accidental release of crude oil and refined fuels into the aquatic environment, continued demand of such fuels--particularly in the transportation sector--pose a continued threat to the aquatic environment throughout their handling, processing, and consumption. Even though measures can be taken to remove the visible layers of fuel in water, it has been shown that constituents of these fuels--that partition into water--can have adverse health effects on the aquatic organisms at low concentrations that are not necessarily predictable through the study of the actual fuel's original composition. Consequently, this renders the need for an …

Impact Of Zinc Oxide Nanoparticles On Green Pea Plant & Seed Quality And Effects On Physiological Traits Of Green Peas, Corn, And Zucchini By Silver Nanoparticles, Arnab Mukherjee

Open Access Theses & Dissertations

The production and use of numerous engineered nanomaterials (ENMs) have increased exponentially over the past decade. Nanoparticles (NPs), ENMs possessing diameter between 1-100 nm, (NPs), are widely used in many applications. Worldwide consumption of NPs has increased their possible release into the environment. This, in turn, has elevated the extent of the potential impacts of NP exposure to living and non-living organisms. This is why the assessment of the impact of NPs on different environmental components, especially on plants, the producer in the food web, has become a very important aspect of nano-ecotoxicology. However, studies focusing on phytotoxicity and effects …