38280-53-4Relevant academic research and scientific papers
Hydrolytic cleavage of pyroglutamyl-peptide Bond. V. Selective removal of pyroglutamic acid from biologically active pyroglutamylpeptides in high concentrations of aqueous methanesulfonic acid
Kobayashi, Junko,Ohki, Kazuhiro,Okimura, Keiko,Hashimoto, Tadashi,Sakura, Naoki
, p. 827 - 831 (2007/10/03)
Application of aqueous methanesulfonic acid (MSA) for selective chemical removal of pyroglutamic acid (pGlu) residue from five biologically active pyroglutamyl-peptides (pGlu-X-peptides, X=amino acid residue at position 2) was examined. Gonadotropin releasing hormone (Gn-RH), dog neuromedin U-8 (d-NMU-8), physalaemin (PH), a bradykinin potentiating peptide (BPP-5a) and neurotensin (NT) as pGlu-X-peptides were incubated in either 70% or 90% aqueous MSA at 25°C. HPLC analysis of the incubation solutions showed that the main decomposition product was H-X-peptide derived from each pGlu-X-peptide by the removal of pGlu. The results revealed that the pGlu-X peptide bond had higher susceptibility than various internal amide bonds in the five peptides examined, including the Trp-Ser bond in Gn-RH, the C-terminal Asn-NH2 in d-NMU-8, and the Asp-Pro bond in PH, whose acid susceptibility is well known. Thus, mild hydrolysis with high concentrations of aqueous MSA may be applicable to chemically selective removal of pGlu from pGlu-X-peptides for structural examinations.
Characterization of the degradation products of luteinizing hormone releasing hormone
Motto,Hamburg,Graden,Shaw,Cotter
, p. 419 - 423 (2007/10/02)
The degradation products of luteinizing hormone releasing hormone [LH/RH; 1; gonadorelin releasing hormone (GnRH); 2] were determined in aqueous solution (pH 6.5) at 25, 37, 50, and 80 °C. The predominant route of degradation involved the cleavage of the 2 to the free acid form in peptides 4 and 10. Racemization of the serine and histidine residues to give peptides 2 and 3 was a second route of degradation.
