A novel peptide QUB-2562, discovered from the skin secretion of the frog, Agalychnis annae

  • Roujia Gong

Student thesis: Masters ThesisMaster of Philosophy


With the increasing problem of resistance to older antimicrobials, and the delay in the development of new antibiotics, there is an urgency to discover some new drugs. During the last few decades, skin secretions of amphibians, especially frogs, were found to be a vast resource of antibiotic agents.

In this project, a novel peptide QUB-2562 derived from the skin secretion of Agalychnis annae was identified by molecular cloning. Solid-phase synthesis was applied to synthesise the novel peptide. After the synthesis, High Performance Liquid Chromatography (HPLC) and Matrix-assisted laser desorption ionisation, time-of-flight (MALDI-TOF) mass spectrometry was used to identify and purify peptide QUB-2562. Then QUB-2562 was tested in several biological experiments and found to inhibit the growth of S. aureus (MIC = 2 µM; MBC = 2 µM), E. coli (MIC = 4 µM; MBC = 4 µM), and C. albicans (MIC = 8 µM; MBC = 16 µM). Meanwhile, its degrees of haemolysis at 2 and 16 µM were only 1% and 10%, respectively, which might be worthy of further exploration.

Thesis embargoed until 31st October 2024
Date of AwardDec 2019
Original languageEnglish
Awarding Institution
  • Queen's University Belfast
SupervisorTianbao Chen (Supervisor), Mei Zhou (Supervisor), Lei Wang (Supervisor) & Xinping Xi (Supervisor)

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