Identification and functional study of a novel bioactive peptide QUB-1761 from the venom of the Brazilian yellow scorpion, Tityus serrulatus

Scorpion venom contains a variety of peptides exerting broad bioactivities. In this thesis, QUB-1761, a non-disulphide bridged peptide (NDBP), was discovered in the venom of the Brazilian yellow scorpion, Tityus serrulatus (T. serrulatus). The peptide was identified through molecular cloning by using a sense primer. The synthetic peptide was obtained by solid phase peptide synthesis (SPPS), followed by purification and confirmation through reversed-phase high performance liquid chromatography (RP-HPLC) and matrix-assisted laser desorption ionisation-time of flight mass spectrometry (MALDI-TOF MS). In broth microdilution assays, QUB-1761 had strong inhibitory effects on both Gram-positive and Gram-negative bacteria (MIC=8 µM for Staphylococcus aureus, MIC=32 µM for Escherichia coli). However, it was of low potency against yeast (MIC=128 µM for Candida albicans). In MTT anticancer cell proliferation and trypan blue exclusion assays, QUB-1761 beyond the concentration of 40 µM can completely kill the human lung cancer cells (NCI-H838). In terms of the haemolytic assays, QUB-1761 showed about 30% haemolysis activity at 64 µM and more than 50% at 128 µM. Nonetheless, QUB-1761 has the potential to be used in the design of drugs to treat bacterial infections or cancer if optimised.<br/><br/><i>Thesis embargoed until 31 December 2026</i>.

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

2021

Author dc:creator

• Wang, Xinyue

Advisors dc:contributor.advisor

• Zhou, Mei
• Chen, Tianbao
• Wang, Lei

• Scorpion venom
• non-disulphide bridged peptide
• Gram-positive and Gram-negative bacteria
• human lung cancer
• haemolysis activity

Language dc:language

eng

Identifier

oai:pure.qub.ac.uk/portal:studenttheses/2a6aa10f-755e-4e1c-b1bb-1f44481a6825

OAI identifier oai:identifier

oai:pure.qub.ac.uk/portal:studenttheses/2a6aa10f-755e-4e1c-b1bb-1f44481a6825