Physical Sciences and Mathematics Commons^™

Synthesis, Reactivity, And Nmr Trends Of Early Transition Metal Compounds, Tabitha Marie Cook

Doctoral Dissertations

This dissertation focuses of three different subjects. The first is the synthesis and characterization of heptacoordinate amidinate compounds. Heptacoordinate compounds are not common, but their structures have been studied. Group 4 amidinate compounds have been used as precursors in the CVD/ ALD processes. Ancillary ligands, such as amidinates, have been used to reduce air-sensitivity of complexes. Reactions of these complexes with water have been used to make metal oxide thin films.

In the first study, the complexes Zr[MeC(NⁱPr)₂]₃Cl [zirconium trisamidinate chloride], Hf[MeC(NⁱPr)₂]₃Cl [hafnium trisamidinate chloride], Zr[MeC(NⁱPr) …

Modeling The 3-Dimensional Structure Of D(Cgcgaattcgcg) And Its 8-Oxo-Da5 Adduct With 1h Nmr Noesy Refinements, Christopher Miles Reynolds

MSU Graduate Theses

Since the characterization of the oligomer d(CGCGAATTCGCG) has been published by Dickerson et al., computational studies have been carried out to produce an accurate 3D model. These models are important for visualizing how certain DNA repair enzymes, such as the glycosylases, recognize sites of damage by signatures of local 3D distortion. Using 1H NOESY-generated internuclear distances to replicate the model of this oligomer and a derivative with an 8-oxo-dA5 lesion, we propose characteristics of helical distortion that DNA glycosylases might use for identifying this form of damage. In addition, this method of comparison can be used to study the repair …

Interaction Of Spliceosomal U2 Snrnp Protein P14 With Its Branch Site Rna Target, William Perea Vargas

Dissertations, Theses, and Capstone Projects

Newly transcribed precursor messenger RNA (pre-mRNA) molecules contain coding sequences (exons) interspersed with non-coding intervening sequences (introns). These introns must be removed in order to generate a continuous coding sequence prior to translation of the message into protein. The mechanism through which these introns are removed is known as pre-mRNA splicing, a two-step reaction catalyzed be a large macromolecular machine, the spliceosome, located in the nucleus of eukaryotic cells. The spliceosome is a protein-directed ribozyme composed of small nuclear RNAs (snRNA) and hundreds of proteins that assemble in a very dynamic process. One of these snRNAs, the U2 snRNA, is …

Evaluating The Role That A Putative Fxiii Binding Site Plays In The Reactivity Of Three Glutamines Within The Coagulation Substrate Fibrinogen Aα (233-425)., Chad A. Stephens

College of Arts & Sciences Senior Honors Theses

Formation of a stable thrombus in vivo depends on the interaction between fibrinogen and the transglutaminase factor XIII (FXIII). Characteristics of blood plasma, such as concentration of Ca2+, are well known to regulate the activation and subsequent reactivity of FXIII. Despite this knowledge, the role fibrin(ogen) plays in modulating FXIII activation and reactivity is not entirely delineated. Currently, the coagulation substrate fibrinogen Aα is proposed to contain a binding site for the active factor XIII with fibrinogen Aα E396 serving a major role. A series of mass spectrometry and NMR spectroscopy studies was conducted to assess whether putative interactions between …

Optimizing Protocols For Carbohydrate Nmr Chemical Shift Computations, Michael Trent Kemp

USF Tampa Graduate Theses and Dissertations

The spectroscopic analysis of cellulose is experimentally challenging while computationally accessible with recent developments in NMR code. However, prior to using density functional theory to calculate the NMR chemical shifts of cellulose, smaller, sugar-like molecule systems need to be benchmarked against experimental values. The quantum mechanical / molecular mechanical (QM/MM) calculations presented herein utilize six test systems: ethanol, pyridine, pyrrolidine, pyrrole, myo-inositol and scyllo-inositol in conjunction with the reference tetramethylsilane used to scale the calculated isotropic shielding tensors to relative chemical shifts. The effect of solvent on calculated NMR chemical shifts has also been investigated with regard to quantity of …

Fundamental Studies Of Humic Acid's Influence On Pollutant Toxicity To Aquatic Organisms, Rachel Dawn Deese

LSU Doctoral Dissertations

The main purpose of the research presented in this dissertation was to further understand the intricate and convoluted interactions between natural organic material, biological entities, and pollutants. This was achieved by utilizing humic acids (HAs) from differing sources, chemically modified humic acid, two biological entities (model biomembranes and Artemia Franciscana), and three types of pollutants (cations, surfactants, and carbon nanotubes). Fluorescence spectroscopy and model biomembranes were used to measure the change in HA’s ability to interact with the biomembranes in the presence of cations. Three differently sourced HAs, chemical modified HAs, and a range of cations were studied to elucidate …

Investigating The Structure Of The Papain-Inhibitor Complex Using Spr And Nmr, Margaret Sara Thomasson

LSU Doctoral Dissertations

Cysteine proteases (CPs) are enzymes with a nucleophilic thiol in their active sites. Inhibitors of cysteine proteases (ICPs) occur naturally in bacterial pathogens and some protozoa. In parasites, ICPs are often virulence factors, contributing to the formation and survival of amastigotes within host cells. These amastigotes have higher CP activity, therefore making both ICPs and CPs potential drug targets. Despite great genetic variability, ICPs contain highly conserved structural features, including a series of defined loops that play a significant role in binding CPs. Papain, a CP from Carica papaya, complexes with ICP from Leishmania mexicana. Although the individual 3-D structures …