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Structural Characterization Of Beta Carbonic Anhydrases From Higher Plants., Michael H. Bracey
Structural Characterization Of Beta Carbonic Anhydrases From Higher Plants., Michael H. Bracey
LSU Historical Dissertations and Theses
It is the goal of this dissertation research to reveal some aspects of the physical nature of spinach carbonic anhydrase as a representative $\beta$CA using the techniques of sequence comparison, molecular biology, and biophysics. Though both $\alpha$ and $\beta$ carbonic anhydrases are zinc dependent metalloenzymes, it is clear that the two isoforms do not adopt the same mechanism for coordinating the active site metal. While $\alpha$CA binds zinc through three histidine ligands, $\beta$CA cannot due to a lack of evolutionarily conserved histidines. Instead, the $\beta$ family has adopted a ligand scheme incorporating a single histidine and two cysteines. This has …
Chiral Recognition With Polymerized Dipeptide Surfactants In Capillary Electrophoresis., Eugene Joseph Billiot
Chiral Recognition With Polymerized Dipeptide Surfactants In Capillary Electrophoresis., Eugene Joseph Billiot
LSU Historical Dissertations and Theses
The research presented in this dissertation involves the use and characterization of polymerized amino acid based surfactants for the enantiomeric separation of chiral compounds using capillary electrophoresis. The first section, Chapter 1, is an introduction to three topics which are relevant to the work presented in this manuscript. The topics include a brief discussion about chirality and chiral recognition, followed by a description of surfactants and micellar systems. The last part of the introduction pertains to capillary electrophoresis and the use of micellar electrokinetic chromatography for enantiomeric separation of chiral compounds. In Chapter 2, the effect of amino acid order …
Antimycobacterial Natural Products From Higher Plants., Charles Lowell Cantrell
Antimycobacterial Natural Products From Higher Plants., Charles Lowell Cantrell
LSU Historical Dissertations and Theses
Two-hundred and thirty crude organic extracts from 118 plant species distributed among ten families of higher plants have been evaluated for antimycobacterial activity against Mycobacterium tuberculosis (H$\sb{37}$Rv) and M. avium using the BACTEC 460 radiorespirometric assay. At 100 $\mu$g/ml, twenty-four and ten of the extracts caused more than 95% inhibition of growth of M. tuberculosis and M. avium, respectively. Bioactive chromatographic fractions of Borrichia frutescens (Asteraceae) provided two new triterpenes and one known cycloartenol. In radiorespirometric bioassays against M. tuberculosis, the new (24R)-24,25-epoxycycloartan-3-one and the known (24R)-24,25-epoxycycloartan-3$\beta$-ol exhibited minimum inhibitory concentrations (MICs) of 8 $\mu$g/ml. In contrast, the new (23R)-3-oxolanosta-8,24-dien-23-ol …
Localization And Biochemical Characterization Of The Cell Division Protein Ftsa In Escherichia Coli., Anand Immaneni
Localization And Biochemical Characterization Of The Cell Division Protein Ftsa In Escherichia Coli., Anand Immaneni
LSU Historical Dissertations and Theses
Cell division protein, FtsA, is an inner membrane protein with a putative ATP binding motif. Although FtsA has been studied genetically, it has not been characterized biochemically. Immunoelectron microscopy with FtsA polyclonal antibodies permitted FtsA to be within the cell. Since native FtsA is present in low amounts, the cellular level of this protein was increased by induction of ftsA from an overexpression plasmid before processing the cells for immunogold labelling. The immunogold particles localized FtsA to the inner cytoplasmic membrane. Immunogold labelling of cells overproducing C-terminal deleted FtsA, displayed the gold particles throughout the cytoplasm. This suggested that the …
Synthesis And Physical Characterization Of Solid-State Materials., Patrick Allen Kolniak
Synthesis And Physical Characterization Of Solid-State Materials., Patrick Allen Kolniak
LSU Historical Dissertations and Theses
Two quantitative X-ray powder diffraction methods were used to analyze Phosphogypsum, a currently underutilized solid by-product of phosphoric acid production. Three kinds of synthetic mixtures were prepared to reflect the variable composition of phosphogypsum: AG (anhydrite and gypsum), QCD (quartz, calcite, and dolomite), and AGQCD. Compositions derived from the Whole Pattern fitting method for the binary and ternary mixtures agreed reasonably well with known values, with residuals $\rm\langle R\sp2\rangle = 0.10$ for eleven AG samples, and $\rm\langle R\sp2\rangle = 0.018$ for thirteen QCD samples. However, in the five-component mixtures, overlap of anhydrite, dolomite and gypsum peaks prevented quantitation. Compositions derived …
Advances In The Chemistry Of Fullerene Fragments., Mark D. Clayton
Advances In The Chemistry Of Fullerene Fragments., Mark D. Clayton
LSU Historical Dissertations and Theses
This dissertation deals with the synthesis and characterization of novel intermediate target molecules that when placed under pyrolytic conditions, yield polynuclear aromatic hydrocarbons that can be identified on the surface of buckminsterfullerene. It also presents some direct applications that have developed from some significant synthetic improvements of key intermediates required for production of novel fullerene fragments. Chapter one presents the synthetic routes used to prepare C32H 12 and attempts toward synthesizing C40H14 and C46H20. The novel C32H12 is only the second known fullerene fragment that contains more than thirty carbon atoms. It is successfully produced by flash vacuum pyrolysis by …