Identification and functional assessment of a bioactive peptide from the skin secretion of the frog, Amolops wuyiensis

Antimicrobial peptides from amphibian skin secretions are promising candidates as alternatives to antibiotics. In this study, the isolated mRNAs from the skin secretion of the frog, Amolops wuyiensis (A. wuyiensis), were subject to ‘shotgun’ cloning and Sanger sequencing methods to identify an antimicrobial peptide, namely QUB-2514, from its biosynthetic precursor-encoding cDNA.

The antimicrobial peptide was then chemically synthesised and purified by solid-phase synthesiser and high-performance liquid chromatography, respectively. Finally, the purified peptide was tested for biological activities, including antibacterial, anti-lung cancer and haemolytic activities. QUB-2514 was found to have the most potent inhibitory and bactericidal effects on Enterococcus coli (E. coli ATCC 8739) (MIC=4 µM, MBC= 8 µM) than Staphylococcus aureus (S. aureus ATCC 6538) (MIC=8 µM, MBC= 16 µM) and Candida albicans (C. albicans ATCC 10231) (MIC=64 µM, MBC= 128 µM).