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

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.<br/><br/>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. <br/><br/>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.

Name dc:type.qualificationname

Master of Philosophy

Level dc:type.qualificationlevel

Masters Thesis

Grantor dc:publisher.institution

Queen's University Belfast

Year dc:date.issued

2017

Author dc:creator

• Maierhaba, Yilihamu

Advisors dc:contributor.advisor

• Shaw, Christopher
• Chen, Tianbao
• Zhou, Mei
• Wang, Lei
• Ma, Chengbang

Language dc:language

eng

Identifier

oai:pure.qub.ac.uk/portal:studenttheses/1c055c4b-356c-4b6c-aa43-74faf602b567

OAI identifier oai:identifier

oai:pure.qub.ac.uk/portal:studenttheses/1c055c4b-356c-4b6c-aa43-74faf602b567