A bioactive peptide, QUB-1813, from the defensive skin secretion of the Chinese Large Odorous Frog, Rana (Odorrana) livida

In this study, “shotgun” cloning was employed to identify a peptide named QUB-1813 from the skin secretion and online BLAST sequence analysis was also performed. The structure of the peptide was initially deduced from cloned precursor-encoding cDNA and confirmed by MALDI-TOF mass spectrometry.

It was then chemically-synthesised by solid phase Fmoc chemistry to provide sufficient material to perform bioassays. <br>The results showed that QUB1813 possessed weak antimicrobial activity against the standard Gram-negative bacterium, Escherichia coli (E. coli), the Gram-positive bacterium, Staphylococus aureus (S. aureus), and the yeast, Candida albicans (C. albicans). The peptide did not inhibit the proliferation of the human cancer cell lines, PC-3, H-157, MB-435s, and U251MG.