Characterisation and bioactivity evaluation of a peptide, Odorrana-S1, from the skin secretion of the frog, Odorrana grahami

Abstract

Amphibian skin secretion is an incredible resource for novel bioactive peptide discovery. Peptides produced from amphibian skin secretion from anuran species demonstrate exceptional antibiotic effects and may ultimately play a central role as alternatives to classical antibiotics as the latter have largely lost their efficacy due to resistance acquisition by target bacteria.

In this study, the discovery of a novel peptide is described from the skin secretion of Odorrana grahami and was named Odorrana-S1. It was successfully cloned by “shotgun” cloning and Sanger sequencing established that it was composed of 14 amino acids. Following synthesis through solid phase peptide synthesis, RP-HPLC purification and MALDI-TOF MS analysis, the peptide was deemed to be of sufficiently high purity for biofunctional analysis. After conducting a series of bioassays including MIC, MTT and haemolysis assays, Odorrana-S1 displayed MICs of >512 μM, no significant performance against cancer cells and no haemolysis of horse red blood cells.
Although Odorrana-S1 did not demonstrate remarkable bioactivities compared with other natural or synthetic antimicrobial peptides (AMPs), it offered a new insight into the effects of structural and physical properties on biological activity which can aid in the design of antimicrobial peptide analogues.

Thesis is embargoed until 31 December 2028.

Date of Award	Dec 2023
Original language	English
Awarding Institution	Queen's University Belfast
Sponsors	China Scholarship Council
Supervisor	Mei Zhou (Supervisor), Tianbao Chen (Supervisor) & Yangyang Jiang (Supervisor)