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Protected Peptides (protected + peptide)
Selected AbstractsA Dde resin based strategy for inverse solid-phase synthesis of amino terminated peptides, peptide mimetics and protected peptide intermediatesJOURNAL OF PEPTIDE SCIENCE, Issue 2 2005Aman Rai Abstract This report describes a Dde resin based attachment strategy for inverse solid-phase peptide synthesis (ISPPS). This attachment strategy can be used for the synthesis of amino terminated peptides with side chains and the carboxyl terminus either protected or deprotected. Amino acid t -butyl esters were attached through their free amino group to the Dde resin. The t -butyl carboxyl protecting group was removed by 50% TFA, and inverse peptide synthesis cycles performed using an HATU/TMP based coupling method. Protected peptides were cleaved from the resin with dilute hydrazine. Side chain protecting groups could then be removed by treatment with TFMSA/TFA. The potential of this approach was demonstrated by the synthesis of several short protected and unprotected peptides in good yield and with low epimerization. Its potential for peptide mimetic synthesis was demonstrated by the synthesis of two peptide trifluoromethylketones. Copyright © 2004 European Peptide Society and John Wiley & Sons, Ltd. [source] Identification of small peptides mimicking the R2 C -terminus of Mycobacterium tuberculosis ribonucleotide reductaseJOURNAL OF PEPTIDE SCIENCE, Issue 3 2010Daniel J. Ericsson Abstract Ribonucleotide reductase (RNR) is a viable target for new drugs against the causative agent of tuberculosis, Mycobacterium tuberculosis. Previous work has shown that an N -acetylated heptapeptide based on the C -terminal sequence of the smaller RNR subunit can disrupt the formation of the holoenzyme sufficiently to inhibit its function. Here the synthesis and binding affinity, evaluated by competitive fluorescence polarization, of several truncated and N -protected peptides are described. The protected single-amino acid Fmoc-Trp shows binding affinity comparable to the N -acetylated heptapeptide, making it an attractive candidate for further development of non-peptidic RNR inhibitors. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. [source] Simulation and Experiment of Temperature and Cosolvent Effects in Reversed Phase Chromatography of PeptidesBIOTECHNOLOGY PROGRESS, Issue 3 2005Kosta Makrodimitris Experiments and simulations have been carried out for several polar protected peptides in reversed phase chromatography in order to demonstrate how simulation can describe the effects of varying temperature and cosolvent fraction. Comparisons of adsorption chemical potentials from mesoscopic simulations and experimental chromatographic retention data show very good agreement with only one temperature-independent solvent parameter from a single peptide. Such simulations should help guide the design of chromatography experiments with biomolecules and predict retention, including conditions for which empirical correlations such as hydrophobicity scales and molecular descriptors have not been developed. [source] Synthesis and secondary structure of loop 4 of myelin proteolipid protein: effect of a point mutation found in Pelizaeus-Merzbacher diseaseCHEMICAL BIOLOGY & DRUG DESIGN, Issue 3 2005E. Trifilieff Abstract:, To study the effects of a point mutation found in Pelizaeus-Merzbacher disease (PMD) on the physicochemical and structural properties of the extracellular loop 4 of the myelin proteolipid protein (PLP), we synthesized the peptide PLP(181,230)Pro215 and one mutant PLP(181,230)Ser215 with regioselective formation of the two disulphide bridges Cys200 -Cys219 and Cys183 -Cys227. As conventional amino acid building blocks failed to give crude peptides of good quality we had to optimize the synthesis by introducing pseudoproline dipeptide building blocks during the peptide elongation. In peptide Pro215 the first bridge Cys200,Cys219 was obtained after air oxidation, but in peptide Ser215 because of aggregation, dimethyl sulfoxide (DMSO) oxidation had to be used. The second bridge Cys183,Cys227 was obtained by iodine oxidation of both Cys (acetamidomethyl, Acm)-protected peptides. The secondary structures of the parent and mutant loops were analysed by circular dichroism (CD) in the presence of trifluoroethanol (TFE) and sodium dodecyl sulphate (SDS) as a membrane mimetic. Analysis of the spectra showed that the content of , -helix and , -sheet varied differently for both peptides in TFE and SDS solutions, demonstrating the sensitivity of their conformation to the environment and the differences in their secondary structure. The ability of both peptides to insert into the SDS micelles was assayed by intrinsic tryptophan fluorescence. [source] | ||||||||||