Identification of a novel peptide, QUB-1172, from the defensive skin secretion of Odorrana schmackeri, and its functional study

Abstract

Antimicrobial resistance is a critical and growing global health threat that results in the decreased effectiveness of antibiotics and other antimicrobial drugs, making it increasingly difficult to treat infectious diseases and leading to higher rates of morbidity, mortality, and healthcare costs. Amphibian skin has been proven as a treasure trove of natural medicine. Many studies show that the antimicrobial peptides (AMPs) collected from amphibians have pharmacological and clinical potential.

This research explored the bioactivity of a novel peptide, QUB-1172, which was identified from the skin secretion of Odorrana schmackeri by “shotgun” cloning, synthesized by SPPS, purified by RP-HPLC and identified by MALDI-TOF mass spectrometry. The bioactivity evaluation included antimicrobial assay, anticancer assay and haemolysis assay at the maximal concentration of 512 μM. The current conducted assay has not presented its bioactivity.

QUB-1172 showed no specific bioactivity against E. coli ATCC 8739, S. aureus ATCC 6538, C. albicans ATCC 10231 and H838 Cell line which might be attributed to the random coil structure and low amphipathicity. The peptide, Rana-BI, which has the most similar sequence to QUB-1172, was proven to be able to inhibit the contraction of rat bladder induced by bradykinin. It was thus indicated that further investigation of the biological activity of QUB-1172, is needed.

Thesis is embargoed until 31 December 2028.

Date of Award	Dec 2023
Original language	English
Awarding Institution	Queen's University Belfast
Supervisor	Lei Wang (Supervisor), Tianbao Chen (Supervisor) & Tao Wang (Supervisor)