Proteins solid-phase sequencing

P] Halstrom, J., Kovdcs, K., Bninfeldt, K. Synthesis of the N-lVityl Hex ieplide Hydrazide Corresponding to the Sequence 152-157 of the Coat Protein of Tbbacco Mosaic Virus. Comparison of the Homogeneous and the Solid Phase Syntheses", Acta Chem. Scand. 1973, 27. 3085-3090. 

The third approach (iii), the solid-phase synthesis, has not been yet implemented for the preparation of protein-like HP-copolymers with heterogeneous blockiness, although the possibility—inherent in this method—to form the macromolecular chains with a well-defined chemical sequence of monomeric units is of great interest for the problem. That is why, these possibilities will also be discussed briefly in Sect. 2.4. 

In the chemical communication many peptide-protein (e.g., peptide hormone agonist) or protein-protein signaling interaction take place. Various photoreactive amino acids, e.g., azido-phenyalanines (Apa, TFApa) [40, 41], benzoyl-phenyalanines (Bpa,p-OH-Bpa) [41,42],trifluorometil-diazirine-phenylalanine (TMDPhe) [43], were developed (Fig. 3), which can be incorporated into any places in peptide sequences by standard solid-phase synthetic techniques. 

Wittmann-Liebold, B., Brauer, D., and Dogpiin, J. M. (1977a). In Solid Phase Methods in Protein Sequence Analysis (A. Previero and M. Previero-Coletti, eds.), p. 219. Elsevier, Amsterdam. 

Sequence inversion and racemization have been associated with uncatalyzed formation of the cyclic dipeptides and has been shown to greatly complicate the kinetics of formation. Cyclic dipeptide formation, by uncatalyzed processes, is rapid enough to pose an apparent threat to the stability of proteins and a possible rationale for the posttranslational N-acetylation of proteins that have been observed in higher organisms. The rate of DKP formation will also depend on the carbonyl ester protecting groups or the structures of the peptide-resin linkage in the solid-phase mode. Furthermore, cyclization is a concentration-independent reaction and demands the use of dilute solutions. ... 

Combinatorial chemistry began with the work of Bruce Merrifield in 1963 to develop a solid-phase peptide synthesizer machine, which was recognized by the awarding of the Nobel Prize in Chemistry in 1984. All proteins are linear sequences... 

Ribonuclease A (RNase A) was selected as the target enzyme for solid-phase synthesis because its sequence was known (Scheme S), 22 25 and an X-ray structure had been deduced. 24 Importantly, it had been shown that this 124-residue protein could be reduced and unfolded and then reoxidized to re-form the four disulfide bonds with recovery of full enzymatic activity. 25 ... 

In addition to incorporating the 4-(2-aminoethyl)dibenzofuran-6-propanoic acid template into small peptides where a reverse turn is desired, we have also recently incorporated this template into a mini-protein called the PIN WW domain. WW domains have a three-stranded antiparallel p-sheet structure that mediates intracellular protein-protein interactions. 31 Substitution of this 3-turn mimetic into loop 1 of the PIN WW domain leads to a folded, three-stranded, antiparallel p-sheet structure with a stability indistinguishable from that of the all a-amino acid sequence. The template-incorporated PIN WW domain (11) was synthesized by an Fmoc-based solid-phase peptide synthesis strategy (Scheme 8), utilizing N-Fmoc-protected 4-(2-aminoethyl)dibenzofuran-6-propanoic acid 10. 11 The synthesis of 10, similar to that of 8, has been published.1 1 ... 

Scheme 6 Combined Solid-Phase and Solution Strategy After Chain Assembly, the Linear Template Sequence Is Cleaved from the Resin, Cyclized in Solution and Re-immobilized on a Resin (Steps a-d) Orthogonal Protection Allows for the Construction of Protein Surface Mimetics, TASP Molecules, or Receptor Mimetics 52 53 ...

For the fast identification of lead compounds for novel, small molecule enzyme inhibitors or other ligands for proteins, the screening of large and diverse arrays of compounds prepared on insoluble supports is one of the most efficient approaches.1-8 Parallel solid-phase synthesis has been found to be particularly well suited for the preparation of such arrays of diverse compounds since multistep synthetic sequences on insoluble supports can be conducted on fully automated synthesizers. 

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