Study On The Interaction Of Three Proteins With Small Ligands By Molecular Spectroscopy

The study on the interaction between protein and small molecules is the important subject in the field of Supermolecular Chemistry, Proteomics and Life Science. It can be helpful to understand the binding nature of the small ligands to protein molecules and to develop new methods for analyzing protein. In this paper, lysozyme, myoglobin and bovine serum albumin were employed as the model proteins to study their interaction mechanism with small molecules such as dyes, drugs and inorganic ion adopting fluorescence, resonance light scattering and chemiluminescence methods. The dissertation includes eight chapters.1. Overview of the interaction protein with ligands. It was summarized the significance for studying the interaction mechanism between protein and small molecules, reviewed the research status for the interaction of protein with small organic molecules and inorganic ions using fluorescence and resonance light scattering methods, and given the research content of the thesis.2. Study on the interaction between lysozyme and bromophenol blue. It was discussed in detail the mechanism of the interaction between lysozyme and bromophenol blue (BPB) by fluorescence and resonance light scattering (RLS) ways. The quenching process of lysozyme-BPB was induced by the static quenching mode to form the nonradiative ground-state complex. The binding parameters such as the binding constant, the number of binding site and the binding mode were calculated. The binding distance from the binding site of BPB on lysozyme molecule to tryptophan residues was obtained using the fluorescence resonance energy transfer theory. The binding system of lysozyme-BPB was applied successfully to determine lysozyme in human saliva and tear samples using RLS method.3. Optical behavior of lysozyme and 4-(2-pyridylazo)-resorcinol. It was described a study on the interaction of lysozyme with 4-(2-pyridylazo)-resorcinol (PAR) by fluorescence and resonance light scattering (RLS) methods. It was proposed that PAR molecules can self-assemble and then form the polymolecular complexes with lysozyme. And it was found that the molecular ratio of lysozyme and PAR arrived to 1:12 the reaction to form the lysozyme-PAR complex got saturated. Based on the formation of lysozyme-PAR polymolecular complex, the RLS singnal of PAR was enhanced obviously and regularly in the presence of lysozyme. The present system was used to deal with lysozyme in hen egg white, human saliva and tear samples, respectively.4. Study on the interaction mechenism of lysozyme and cephalosporin analogues. The interaction between lysozyme and cephalosporin including cefadroxyl, cefradine, cefuroxime, cefotaxime and ceftriaxone was studied by fluorescence combined with fluorescence energy transfer theory. It was clearly shown that the intrinsic fluorescence of lysozyme was quenched by cephalosporin through the static quenching ang nonradiative energy transferring procedure. It was suggested that cephalosporin probably bound to the active site near Trp62 in lysozyme. It was observed that the binding capability of cephalosporin to lysozyme was in the order of ceftriaxone > cefuroxime > cefotaxime > cefradine > cefadroxyl and almost consistent with its antibacterial ability.5. Investigation of the interaction between bovine serum albumin and cephalosporin. It was depicted the study on the interaction mechanism between bovine serum albumin and cephalosporin analogues adopting fluorenscence spectroscopy. It was also found that the order of the binding ability of cephalosporin to BSA was close to its antibacterial capability.6. Chemiluminescence behavior for the interaction of myoglobin with NO₂^- anion. A new chemiluminescence system luminol-myoglobin was introduced to the determination of NO₂^- anion in human urine and tap water samples.7. Study on the interaction between myoglobin and sudan dyes by chemiluminescence. The new method of chemiluminescence combined with flow-injection was adopted to determine sudan I in the contaminated hot chilli products using luminol-myoglobin system.8. Conclusions...