Glutaminyl

L-pyroglutamyl-L-glutaminyl-L-aspartyl-L-tyrosyl-L-threonyl-glycyl-L-tryptophanyl-... 

L-Pyroglutamyl-L-glutaminyl-L-aspartyl-L-tyrosine azide L-Threonyl-glycyl-L-tryptophanyl-L-methionyl-L-aspartyl-L-phenylalaninamide Pyridine sulfuric anhydride Sodium carbonate... 

Benzylmercaptopropionyl-L-tyrosyl-L-phenyalanyl-L-glutaminyl-L-asparaginyl-S-benzyl-L-cysteinyl-L-prolyl-N-tosyl-D-arginyl glycinamide Sodium Ammonia Acetic acid... 

The mixture is allowed to stand for 2 days at 20°C, after which twice its volume of ethyl-acetate is added and the resultant precipitate then washed with warm methanol. There are obtained 45 parts by weight of N-carbobenzoxy-S-benzyl-L-cysteinyl-L-phenylalanyl-L-phenylalanyl-L-glutaminyl-L-asparaginyl-S-benzyl-L-cysteinyl-L-prolyl-e-N-p-toluenesulfonyl-L-lysyl-glycinamide MP 222 C. 

Preparation of L-Cysteinyl-L-Phenylalanyl-L-Phenylalanyl L-Glutaminyl-L-Asparaginyl-L-... 

N-Carbobenzoxy-L-glutaminyl-L-asperaginyl-S-benzyl-L-cystainyl azide N-Carbobenzoxy-S-benzyl-L-cysteinyl-L-tyrosyl-L-phanylalanine azide Sodium Ammonia... 

Z-Gln-Val-OMe[L-Yaline, A,-[A72-[(phenylmethoxy)-carbonyl]-L-glutaminyl]-, methyl ester] A 77%... 

The method illustrated here does have, however, several excellent features.10 The peptide yields are very good even in the synthesis of asparaginyl and glutaminyl peptides, which are ordinarily very difficult to prepare in reasonable yield. Furthermore, the by-products are all water-soluble and, therefore, easily removed from the product peptide derivative. One recrystallization, even under conditions of almost... 

CN 5-oxo-L-prolyl-L-glutaminyl-L-a-aspartyl-O-sulfo-L-tyrosyl-L-threonylglycyl-L-tryptophyl-L-methionyl-L-a-aspartyl-L-phenylalanin amide... 

CN L-cysteinyl-L-tyrosyl-L-isoleucyl-L-glutaminyl-L-asparaginyl-L-cysteinyl-L-prolyl-L-leucylglycinamide cyclic (1—>6)-disulfide... 

Lamour V., Quevillon, S., Diriong, S., N Guyen, V. C., Lipinski, M. and Miranda, M. (1994), Evolution of the Glx-tRNA synthetase family the glutaminyl enzyme as a case of horizontal gene transfer , Proc. Natl. Acad. Sci. USA, 91, 8670. 

Schilling, S., Hoffmann, T., Rosche, F., Manhart, S., Wasternack, C. and Demuth, H. U. Heterologous expression and characterization of human glutaminyl cyclase evidence for a disulfide bond with importance for catalytic activity. Biochemistry 41 10849-10857,2002. 

The symmetrical anhydride is prepared using dicyclohexylcarbodiimide in dichloromethane, the urea and solvent are removed, and the anhydride is dissolved in dimethylformamide and added to the peptide-resin (see Section 2.5). The anhydride is a more selective acylating agent than the 0-acylisourea and, thus, gives cleaner reactions than do carbodiimides, but twice as much amino-acid derivative is required, so the method is wasteful. It avoids the acid-catalyzed cyclization of terminal glutaminyl to the pyroglutamate (see Section 6.16) and is particularly effective for acylating secondary amines (see Section 8.15). 

A. B. Robinson, C. J. Rudd, Deamidation of Glutaminyl and Asparaginyl Residues in Peptides and Proteins , Curr. Topics Cell. Regul. 1974, 8, 247-295. 

H. T. Wright, Nonenzymatic Deamidation of Asparaginyl and Glutaminyl Residues in Proteins , Crit. Rev. Biochem. Mol. Biol. 1991, 26, 1-52. 

Glutaminyl-tRNA and Asparaginyl-tRNA Biosynthetic Pathways... 

Nonenzymatic Deamidation of Glutaminyl and Asparaginyl Residues in Protein 387... 

Glutaminyl-tRNA Synthetase Direct Formation of Gln-tRNA° " 388... 

Evolution of the tRNA Glutaminylation and Asparaginylation Pathways, and the Late... 

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