Discovery of bioactive peptides from amphibian skin secretion

Among these, bioactive peptides in special skin secretions produced by frogs have been considered to be one of the rich natural sources for developing new drugs in the future.<br><br>In this thesis, several bioactive peptides were identified from the skin secretions of frogs by using RP-HPLC and molecular cloning. Then these peptides were synthesised by solid phase peptide synthesis (SPPS) for researching their biological functions. <br><br>In Chapter 3, a novel peptide, phylloseptin-PV1, was discovered and identified from the defensive skin secretion of the White-lined leaf frog, Phyllomedusa vaillantii.

It was found not only to demonstrate potent antimicrobial activity against planktonic ESKAPE strains and the yeast, C. albicans, but also inhibited and eradicated the biofilm of S. aureus and MRSA. Therefore, a mice model was used for evaluating its further in vivo antimicrobial activity. <br><br>In Chapter 4, a novel dermaseptin peptide, QUB-2522, was identified from the defensive skin secretion of the Northern orange-legged leaf frog, Phyllomedusa hypochondrialis.