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Modeling Congenital Disorders Of Glycosylation In Caenorhabditis Elegans: Genetic Influences And Structural Consequences Of N-Linked Glycosylation, Weston Booth Struwe

Doctoral Dissertations

The attachment of oligosaccharides to the amide nitrogen of asparagine side chains in proteins is a fundamental process occurring in all metazoans. This process, known as N-glycosylation, is complex and is achieved by the precise interactions of various cellular components. The initial stage of N-glycosylation occurs in the endolasmic reticulum and is preserved among eukaryotes. Glycans are further developed in the Golgi and the structural complexity depends greatly on the animal species, tissue and developmental stage. Oligosaccharides are unique biomolecules because unlike DNA or proteins, no primary sequence exists nor is its' synthesis template driven. A major goal of glycobiologist …

Glycan Characterizations With Application In Metal Ion Binding, The 1918 Influenza Virus Neuraminidase Formation And Human Receptors, Hui Zhou

Doctoral Dissertations

The EP glycoprotein, the major protein component isolated from the EP fluid of the mollusc, Mytilus edulis, is known to bind many metal ions and to contain 14.3% of carbohydrate in weight. To structurally evaluate the sugar function of this glycoprotein, a new mass spectrometry-based strategy was applied with a focus on the comprehensive characterization of its N-glycans. This included: (a) accurate mass measurement and GC/MS to determine the monosaccharide compositions; (b) positive ion CID-MS n to disassemble the deuterated permethylated derivates (CD3 ) to reveal the antenna sequence, and natural methoxyl group location; (c) negative ion CID-MSn on native …

Chemical Sensors Based On Swellable Polymer Microparticles And Molecular Imprinted Polymers, John Ong'any Osambo

Doctoral Dissertations

Swellable thermoresponsive and lightly cross-linked polymer microparticles were prepared for the development of chemical sensors for various target analytes. The swelling and shrinking of the polymer particles as a function of concentration of target analytes has been investigated using turbidity and fluorescence measurements at suitable pH values.

Chemical sensors that respond to transition metal ions such as Cu 2+, Ni2+, Zn2+, and Pb2+ were prepared by copolymerizing N-Isopropylacrylamide (NIPAAm) with ligands such as; 2,2'-acylamidodiacetic acid (AIDA), dibutyl-2,2'-(3 vinylphenylazanediyl) diacetate (DVPAA), N-((4'-methyl-2,2'-bipyridin-4yl)methyl)-N-propylacrylamide (NMPPAAm), and N,N-bis(pyridine-2-ylmethyl)prop-2-en-1-amine (NBPMPA). The microparticles were either labeled with 9-vinylanthracene (9-VA)/2-Naphthylmethacrylate (2-NMA), or fluorescein o-acrylate/methacryloxethyl thiocarbonyl rhodamine B …

The Measurement Of Volatile Organic Compounds During Icartt 2004 And Experimental Studies Of Chlorine Atom Reactions With Alpha- And Beta-Pinene, Leif Carsten Nielsen

Master's Theses and Capstones

Proton transfer reaction mass spectrometry (PTR-MS) has been shown to be a reliable and efficient method for determining atmospheric mixing ratios of volatile organic compounds (VOCs). As a part of AIRMAP, two PTR-MS instruments were used in field and laboratory studies. A high sensitivity instrument showed improved limits of detection by 3-5 times when compared to a standard sensitivity instrument. Agreement for quantification of VOCs by PTR-MS to other methods was good. Average atmospheric mixing ratios, diurnal profiles, and deposition velocities of methanol, acetone, acetaldehyde, acetic acid, isoprene, alpha-pinene, beta-pinene, methylethyl ketone, methylvinyl ketone and methacrolein were determined at two …

Development Of Microwave-Assisted Methods To Aid In Carbohydrate Analysis, Stephanie Maniatis

Master's Theses and Capstones

This study involved development of three high-throughput chemical techniques to assist in carbohydrate analysis. The methods utilized both microwave radiation and a volatile organic base to achieve short reaction times and high product yield. Two methods, one reductive and one non-reductive, released intact O-glycans for structural analysis, and one method aided in determination of the site of O-glycosylation on the peptide.

Optimal reaction conditions for each method were determined on standard glycoproteins. In comparison to common release methods, microwave-assisted reductive O-glycan release provided higher yields of O-glycans in every case. O-glycans were released rapidly and were able to be subsequently …

N-Linked Glycans Characterization And Biomarker Discovery By Sequential Mass Spectrometry, Hongqin (Jenny) Jiao

Master's Theses and Capstones

N-linked glycans from a well-studied glycoprotein, (hen albumin) were characterized using ion trap MS (MSn) without chromatographic separation. From the spectral profile, ten major ion compositions were selected for study, which resulted in the characterization of 37 isomeric structures, 16 of which were previously unreported. These findings were compared with previously reported studies using different analytical strategies: IMMS, MS/MS. MSn not only identifies but also structurally characterizes components in the absence of any adjunct instrumentation. Selected examples have been detailed.

A major challenge for adult stem cell (ASC) research is the lack of specific biomarkers for their identification and isolation. …

Design And Construction Of A Chemical Ionization Mass Spectrometer For Ambient Nitryl Chloride Analysis, Leanna Conway

Master's Theses and Capstones

Ambient measurements of trace gas phase species in the Earth's troposphere continue to present an interesting analytical challenge. Instruments must have sufficient sensitivity to monitor low concentrations without compromising the specificity necessary to distinguish the analyte of interest from a complex matrix. A chemical ionization mass spectrometer (CIMS) has been designed and constructed to satisfy these criteria.

Upon validation, the CIMS will assist in the elucidation of the complex chemistry in the troposphere resulting from the influence of urban pollution and marine environment. The CIMS is currently configured to operate in the negative ion mode and employs I- as the …