Studies on a bioactive peptide QUB-2044 from the skin secretion of the Chinese frog, Odorrana schmackeri

  • Yilihamu Maierhaba

Student thesis: Masters ThesisMaster of Philosophy


Nature has been recognised as the most bountiful source for new therapeutics, among which amphibians have been the focus of research in the search for new compounds with biological activities as a result of the abundant bioactive contents of their skins. So far, a great number of pharmacological and antimicrobial peptides (AMPs) have been successfully isolated and identified from the skin and associated secretions of amphibians. Furthermore, some of these peptides have been recognised as significant novel drug leads.

This thesis focused on the study of an AMP from the defensive skin secretions of Odorrana schmackeri. The precursor structure was identified by a strategy of molecular cloning and was subjected to an NCBI-BLAST search and CLUSTAL OMEGA sequence alignment, from which the amino acid sequence of the mature peptide was deduced as: GILKGILGMGKNLVCGLSGLC.

The peptide was synthesised using Solid Phase Peptide Synthesis and subjected to a range of biological assays. In the antimicrobial assay, the synthetic peptide exerted a strong inhibitory activity against S.aureus and a relatively moderate one against E.coli and C.albicans with the MIC values being 16 μM, 32 μM and 32 μM, respectively, and showed mild cytotoxicity against red blood cells at these concentrations. However, the peptide did not show significant anti-cancer activity.
Date of Award29 Aug 2017
Original languageEnglish
Awarding Institution
  • Queen's University Belfast
SupervisorChristopher Shaw (Supervisor), Tianbao Chen (Supervisor), Mei Zhou (Supervisor), Lei Wang (Supervisor), Yuxin Wu (Supervisor), Chengbang Ma (Supervisor), Xinping Xi (Supervisor) & Lei Li (Supervisor)

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