Pyroglutamyl peptides

T. Hashimoto, K. Ohki, N. Sakura, Hydrolytic Cleavage of Pyroglutamyl-Peptide Bond. I. The Susceptibility of Pyroglutamyl-Peptide Bond to Dilute Hydrochloric Acid , Chem. Pharm. Bull. 1995, 43, 2068-2074. 

Natural Occurrence of Pyroglutamic Acid and Pyroglutamyl Peptides... 

Pyroglutamyl peptides are synthetically accessible either by side-chain cyclization of related glutaminyl and glutamyl peptides or by direct acylation of suitably protected peptides with Na-protected or unprotected pyroglutamic acid. 

Pyroglutamyl Peptides as Side Products in Peptide Synthesis... 

The high tendency of glutamine and to a lesser extent of glutamic acid and related derivatives to form pyroglutamic acid which is exploited for the synthesis of pyroglutamyl peptides (Section 6.7.1.1.1), at the same time represents a source of undesirable side reactions in peptide chemistry (for reviews, see refs 16-18 ). 

Enzymatic Digestion of Pyroglutamyl Peptides General Procedure ... 

L. Prokai, X.-D. Ouyang, W.-M. Wu, and N. Bodor, Chemical delivery system to transport a pyroglutamyl peptide to the central nervous system, J. Am. Chem. Soc. 776 2643 (1994). 

Orlowska A, Witkowska E, Izdebski J (1987). Sequence dependence in the formation of pyroglutamyl peptides in solid phase peptide synthesis. Int. J. Peptide Protein Res. 30 141-144. 

Pelvetin, pGlu-Gln-Ala-OH, a naturally occurring pyroglutamyl peptide isolated from algae. 

Pyroglutamyl peptides, peptides bearing pyroglutamic acid residues at the N-terminal position of the peptide chain. Pyroglutamyl acid formation of N-terminal glutamine residues catalyzed... 

Proline iminopeptidase [L-Prolylpeptide hydrolase] (3.4.11.5) is produced. [Formerly EC3.4.1.4.] Pyroglutamyl aminopeptidase [L-Pyroglutamyl-peptide hydrolase, Pyrrolidone-carboxylate peptidase] (3.4.11.8) is produced. [Removes pyroglutamate from various penultimate amino acid residues except L-proline. Occurs in Pseudomonas, Bacillus subtilis, rat liver.]... 

Peptides containing proline, including bradykinin and substance P, have low sensitivities resulting from shuctural limitations caused by the amido nitrogen being unavailable for Cu(II) complexation [155]. This type of structural limitation is not encountered with pyroglutamyl peptides or those containing disulfide bonds. 

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