Structure and Dynamics of Macromolecules: Absorption and Fluorescence Studies

Light absorption by a moleculeJablonski diagram or diagram of electronic transitions. Singlet and triplet states. Forbidden and non forbidden transitions.Reading the Jablonski diagram. Chemical bonds. Absorption Spectroscopy. Fluorescence: Principles and observables Fluorescence properties. Fluorophores: Descriptions and properties.Types of fluorophores. Effect of the environment on the fluorescence observables. Fluorescence quenchingCollisional quenching: the Stern-Volmer relation. The different types of dynamic quenching. Static quenching.Comparison between dynamics and static quenching.Combination of dynamic and static quenching. Thermal intensity quenching. Photoquenching.Fluorescence polarizationAim and definition. Principles of polarization or of photoselection.Absorption transitions and excitation polarization spectrum. Fluorescence depolarization.Fluorescence anisotropy decay time.Depolarization and energy transfer.Forster energy transferPrinciples. Energy transfer parameters.Relation between energy transfer and static quenching. Origin of protein fluorescenceDescription of the structure and dynamics of &agr;1- acid glycoprotein by fluorescence studiesMethods. Fluorescence properties of TNS bound to sialylated &agr;1-acid. Fluorescence properties of calcofluor bound to &agr;1-acid glycoprotein. Fluorescence properties of the Trp residues in &agr;1-acid glycoprotein. Förster energy transfer experiments from Trp residues to calcofluor white. Relation between the secondary structure of carbohydrate residues of &agr;1-acid glycoprotein and the fluorescence of the Trp residues of the protein. Effect of the secondary structure of carbohydrate residues of &agr;1-acid glycoprotein on the local dynamics of the protein.Tertiary structure of &agr;1-acid glycoprotein: first model describing the presence of a pocket. Are there any other alternative fluorescence methods other than the QREA or the Weber's method to put into evidence the presence of a pocket within &agr;1-acid glycoprotein? Experiments giving proofs of the presence of a pocket within &agr;1-acid glycoprotein.Homology modeling of &agr;1- acid glycoprotein.Dynamics of Trp residues in crystals of human &agr;1- acid glycoprotein. Structural studies of human &agr;1-acid glycoprotein followed by X-rays scattering and transmission electron microscopy. Structure and dynamics of hemoglobin subunits and of myoglobin Dynamics of Trp residues in hemoglobin and in its subunits. Properties of tprotoporphyrin IX in different solvents and in apomyoglobin. Dynamics of protoporphyrin IX embedded in the heme.Dynamics of the protein matrix and the heme pocket.Significance of the upward curvature.Effect of sucrose on the bimolecular diffusion constant. Fluorescence fingerprints of animal and vegetal species and/or varietiesFluorescence fingerprints of Eisenia fetida and Eisenia andrei. Structural characterization of varieties of crops among a species and of genetically modified organisms: a fluorescence study.