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Expressed Peptide (expressed + peptide)
Selected AbstractsPolypeptide synthesis using an expressed peptide as a building block for condensation with a peptide thioester: Application to the synthesis of phosphorylated p21Max protein(1,101)JOURNAL OF PEPTIDE SCIENCE, Issue 9 2001Toru Kawakami Abstract An expressed peptide proved to be useful as a building block for the synthesis of a polypeptide via the thioester method. A partially protected peptide segment, for use as a C -terminal building block, could be prepared from a recombinant protein; its N -terminal amino acid residue was transaminated to an ,-oxoacyl group, the side-chain amino groups were then protected with t -butoxycarbonyl (Boc) groups, and, finally, the ,-oxoacyl group was removed. On the other hand, an O -phosphoserine-containing peptide thioester was synthesized via a solid-phase method using Boc chemistry. These building blocks were then condensed in the presence of silver ions and an active ester component. During the condensation, epimerization at the condensation site could be suppressed by the use of N,N -dimthylformamide (DMF) as a solvent. Using this strategy, a phosphorylated partial peptide of the p21Max protein, [Ser(PO3H2)2,11]-p21Max(1,101), was successfully synthesized. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd. [source] Peptidomic analysis of the larval Drosophila melanogaster central nervous system by two-dimensional capillary liquid chromatography quadrupole time-of-flight mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 2 2005Geert Baggerman Abstract Peptides are the largest class of signalling molecules found in animals. Nevertheless, in most proteomic studies peptides are overlooked since they literally fall through the mazes of the net. In analogy with proteomics technology, where all proteins expressed in a cell or tissue are analyzed, the peptidomic approach aims at the simultaneous visualization and identification of the whole peptidome of a cell or tissue, i.e. all expressed peptides with their post-translational modifications. In this paper we describe the analysis of the larval fruit fly central nervous system using two-dimensional capillary liquid chromatography/quadrupole time-of-flight tandem mass spectrometry (LC/Q-TOF-MS/MS. Using the central nervous systems of only 50 larval Drosophila as starting material, we identified 38 peptides in a single analysis, 20 of which were not detected in a previous study that reported on the one-dimensional capillary LC/MS/MS analysis of the same tissue. Among the 38 sequenced peptides, some originate from precursors, such as the tachykinin and the IFamide precursor that were entirely missed in the first study. This clearly demonstrates that the two-dimensional capillary LC approach enhances the coverage of the peptidomic analysis. Copyright © 2005 John Wiley & Sons, Ltd. [source] Selection and mass spectrometry characterization of peptides targeting semiconductor surfacesBIOTECHNOLOGY & BIOENGINEERING, Issue 6 2009Elias Estephan Abstract We report on elaboration of 12-mer peptides that reveal specific recognition for the following semiconductor (SC) surfaces: GaAs(100), InAs(100), GaN(0001), ZnSe(100), ZnTe(100), GaAs(111)A, GaSb(100), CdSe(100). A M13 bacteriophage library was used to screen 109 different 12-mer peptides against these substrates to finally isolate, in maximum six amplification cycles, peptides that bind to the target surfaces. The specific peptides for the InAs and ZnSe surfaces were obtained. Contrary, for the other SC surfaces several peptides with high affinities have been isolated. Aiming for a better specificity, when the phage display has been conducted through six cycles, the screening procedure got dominated by a phage present in the M13 bacteriophage library and the SVSVGMKPSPRP peptide has been selected for different SCs. The high amplification potential of this phage has been observed previously with different targets. Thus, precaution should be undertaken in defining adhesion peptides with the phage display technique and real affinity of the obtained biolinkers should be studied with other methods. We employed mass spectrometry (MALDI-TOF/TOF) to demonstrate the preferential attachment (or not) of the SVSVGMKPSPRP peptide to the different SC surfaces. This allows us to define a realistic selection of the expressed peptides presenting affinity for the studied eight SC surfaces. We demonstrate that with increasing the dielectric constants of the employed solvents, adhesion of the SVSVGMKPSPRP peptide onto GaN(0001) is hindered. Biotechnol. Bioeng. 2009; 104: 1121,1131. © 2009 Wiley Periodicals, Inc. [source] | ||||||||||