: A bioactive peptide from the frog skin secretion of Hylarana guentheri

  • Ziyu Ling

Student thesis: Masters ThesisMaster of Philosophy


Antimicrobial peptides (AMPs) are a sufficient and diverse group of molecules that are derive from various invertebrate, plant and animal species. AMPs possess a variety of biological activity, such as anticancer, antivirus and so on. Nowadays, a growing number of AMPs are considered as promising candidate of new drug.

This thesis focused on the antimicrobial peptide (QUB-1439) which was isolated from the skin secretion of Hylarna guentheri. It is the first time to identify the biosynthetic precursor encoding cDNA of QUB-1439 from the skin secretion-derived cDNA library though the mature peptide sequence, FLPLLFGAISHLL-NH2, has been identified before. Subsequently, QUB-1439 was synthesised by Tribute peptide synthesiser. Then, MALDI-TOF was used to check the molecular weight of the synthetic peptide. The crude peptide was purified by RP-HPLC. Finally, a series assays were performed to test the bioactivities of purified QUB-1439, including antimicrobial assay, anticancer assay and haemolysis assay. The results showed that QUB-1439 has ability to inhibit the growth of Gram-positive bacteria, the MIC of QUB-1439 against S. aureus is 16 μM. QUB-1439 does not exhibit toxicity and it has a weak effect on inhibition of cancer cell growth. Because QUB-1439 has these promising properties, it could be developped into a novel drug.
Date of AwardAug 2018
Original languageEnglish
Awarding Institution
  • Queen's University Belfast
SupervisorTianbao Chen (Supervisor), Xinping Xi (Supervisor), Lei Wang (Supervisor), Mei Zhou (Supervisor), Chengbang Ma (Supervisor), Yuxin Wu (Supervisor), Lei Li (Supervisor) & Christopher Shaw (Supervisor)

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