A peptide, QUB-1420, from the defensive skin secretion of Heilongjiang Brown Frog Rana amurensis

The mature peptide was isolated and identified using a kit with provided UPM primer and a degenerate primer that was designed to a segment of 5’-untranslated regions of cDNAs, which were previously cloned from the skin of a closely-related Asian Species, by performing rapid amplification of cDNA ends (RACE) method. After that, solid phase Fmoc-based chemistry method was used to synthesise the peptide for the following functional experiments.

The reverse-phase HPLC was employed to purify the synthetic peptide products. After a range of bioassays assessment, the antimicrobial, anticancer, protease inhibitory, and myotropic bioactivities of QUB1420 were investigated, However, QUB1420 did not display any bioactivity in the functional assays, whilst it may still have a specific bio-target on some other tissues, cells or hosts.