A novel bioactive peptide from the skin secretion of the Large Chinese Odorous frog, Rana (Odorrana) livida

  • Ji Zhang

Student thesis: Masters ThesisMaster of Philosophy


Natural products are potential sources for the discovery of new drugs. There are many plants and animals, including amphibians, which have naturally occurring substances in them; such substances could to lead to the discovery of exciting new drugs. Amphibian skin secretions contain many bioactive compounds, for example: biogenic amines, alkaloids and steroids, peptides and proteins all of which would have potential medical applications.
In this study, a cDNA encoding novel peptide was discovered from the skin secretion of the Large Chinese Odorous frog, Rana (Odorrana) livida by using the molecular cloning assay. The novel peptide was consisting of 13 amino acid residues with a single disulphide bridge between Cys8 and Cys13 which is a typical Kunitz trypsin inhibitor motif (-CKAAFC-). This novel peptide was found to be a potent inhibitor of trypsin with a Ki value of 7.27±0.45 μM. Subsequently, this peptide was also found to display potential inhibitory activity against E. coli, C. albicans and a weak effect against S. aureus. Meanwhile, it showed weak haemolytic activity at concentrations up to 512 μM. Due to the trypsin inhibitory and antimicrobial effects, this novel peptide could be a candidate for drug discovery and be a template for drug design.
Date of AwardJul 2018
Original languageEnglish
Awarding Institution
  • Queen's University Belfast
SupervisorMei Zhou (Supervisor), Lei Wang (Supervisor), Chengbang Ma (Supervisor), Tianbao Chen (Supervisor) & Christopher Shaw (Supervisor)

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