Part 1: Raman spectroscopy of mass selected metal clusters and Part 2: Conformational studies of turns in peptides by vibrational CD.
Item
-
Title
-
Part 1: Raman spectroscopy of mass selected metal clusters and Part 2: Conformational studies of turns in peptides by vibrational CD.
-
Identifier
-
AAI9618123
-
identifier
-
9618123
-
Creator
-
Zhou, Qinwei.
-
Contributor
-
Advisers: Max Diem | John Lombardi
-
Date
-
1996
-
Language
-
English
-
Publisher
-
City University of New York.
-
Subject
-
Chemistry, Biochemistry | Chemistry, Physical
-
Abstract
-
This dissertation includes two parts of work which were done in two different labs. The first part is focused on Raman Spectroscopy of Mass Selected Metal Clusters in Argon Matrices. The second part is concentrated on Synthesis and Conformational Studies of Turns in Peptides by Vibrational Circular Dichroism.;A principal goal of metal cluster research is a better understanding of the structural properties of these species as a function of cluster size and metal type. In order to achieve this, an ion sputtering cluster deposition source has been successfully built in the lab. Three different clusters (Vanadium dimers, Niobium dimer and Zirconium dimer) in argon matrices have been studied by both Raman Spectroscopy and Scattering Depletion Spectroscopy. We have observed the first absorption spectra of these dimers which are free from interference from atoms or higher mass clusters. Raman spectra obtained throughout the blue-green and red region are in good accord with the optical absorption data.;Vibrational spectroscopy has become one of the common techniques to determine the structure and dynamics of biological molecules and to monitor their conformational changes. Several model peptides are designed with two cysteine residues on both N- and C-terminals which can be cyclized by ringclosure of the S-S disulfide bond between cysteines. Both linear and cyclized peptides are synthesized by step-wise Solid Phase Peptide Synthesis. Conformational changes of these small peptides with both different amino acids between two cysteines and various chemical environment are monitored by VCD. The variety of solvent properties can be used as a probe, which can help us to understand the driving force in peptide folding. The conformation difference between linear and cyclized peptides have been studied. Furthermore, the factor whether D- or L-amino acid residue in peptides have been proven to play a major role in determining the conformation of peptides. Structures from such an analysis consist with that from other techniques. The computed spectra based on Coupled Oscillator Model further confirmed structures from observed VCD.
-
Type
-
dissertation
-
Source
-
PQT Legacy CUNY.xlsx
-
degree
-
Ph.D.
