Amphibian skin secretion is one of the richest sources for antimicrobial peptides (AMPs) which have potent bioactivity and pharmaceutical value for new drug development. In this thesis, QUB-1452, an AMP, was isolated and characterised from the skin secretion of Rana amurensis. The peptide is composed of 13 amino acid residues, FLPVLISLIGRLL, and is C-terminally amidated. The structure and functions of QUB-1452 were identified via nucleotide/amino acid sequencing and bioactivity analyses. The results showed that QUB-1452 had relatively strong antimicrobial activity against S. aureus (Staphylococcus aureus) and C. albicans (Candida albicans) with minimal inhibitory concentrations of 8 µmol/L and 16 µmol/L respectively, while it had little effect on the growth of E. coli (Escherichia coli). In addition, QUB-1452 had high haemolytic activity at high concentrations, whereas the haemolytic activity was relatively low at the minimal inhibitory concentrations against S. aureus and C. albicans at 3.3% and 6.6%, respectively. Moreover, the peptide had no effect on cancer cells. These data demonstrate the potential of amphibian skin secretions to provide novel natural peptide templates for biological evaluation.
|Date of Award||29 Aug 2017|
- Queen's University Belfast
|Supervisor||Christopher Shaw (Supervisor), Tianbao Chen (Supervisor), Yuxin Wu (Supervisor), Mei Zhou (Supervisor) & Lei Wang (Supervisor)|