Tryptic digestion of peptides corresponding to modified fragments of human growth hormone-releasing hormone.

• Authors: Ewa Witkowska , Alicja Orłowska , Jan Izdebski
• Languages of publication: EN

Abstracts

EN

The objective of this study was to examine the degradation of short peptides corresponding to modified fragments of human growth hormone-releasing hormone by trypsin. Six analogues of pentapeptide 9-13 of human growth hormone-releasing hormone containing homoarginine, ornithine, glutamic acid, glycine, leucine or phenylalanine residue in position 11, two analogues of hexapeptide 8-13 of human growth hormone-releasing hormone and two analogues of heptapeptide 7-13 of human growth hormone-releasing hormone containing homoarginine or glycine residue in position 11 were obtained. The peptides were subjected to digestion by trypsin and the course of reaction was monitored using HPLC. It was found that the rate of hydrolysis of the Lys12-Val13 peptide bond depends on the amino-acid residue preceding Lys12. The extension of the peptide chain towards the N-terminus by introduction of consecutive amino-acid residues corresponding to the human growth hormone-releasing hormone sequence accelerates the hydrolysis process. These results may be of assistance in designing new analogues of human growth hormone-releasing hormone, more resistant to the activity of proteolytic enzymes.

Keywords

EN

P2 position; tryptic digestion; hGH-RH fragments

• Publisher: Polish Biochemical Society
• Journal: Acta Biochimica Polonica
• Year: 2004
• Volume: 51
• Issue: 1
• Pages: 51-56

Dates

published

2004

received

2003-10-31

revised

2004-02-04

accepted

2004-02-08

Contributors

author

Ewa Witkowska

• Laboratory of Peptides, Faculty of Chemistry, Warsaw University, L. Pasteura 1, 02-093 Warszawa, Poland

author

Alicja Orłowska

• Laboratory of Peptides, Faculty of Chemistry, Warsaw University, L. Pasteura 1, 02-093 Warszawa, Poland

author

Jan Izdebski

• Laboratory of Peptides, Faculty of Chemistry, Warsaw University, L. Pasteura 1, 02-093 Warszawa, Poland

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