{"id":{"repo_id":"qu-belfast","oai_identifier":"oai:pure.qub.ac.uk/portal:studenttheses/7776ef42-e321-4153-b1af-5e78bdb6c681"},"canonical_url":"https://search.dev.ndltd.org/etd/qu-belfast/oai:pure.qub.ac.uk/portal:studenttheses/7776ef42-e321-4153-b1af-5e78bdb6c681","repository":{"repo_id":"qu-belfast","name":"Queen's University Belfast","base_url":"https://pureadmin.qub.ac.uk/ws/oai"},"display":{"title":"The discovery of a novel peptide, QUB-2274, from the defensive skin secretion of Rana amurensis","abstract":"Based on extensive natural drug investigations, frog skin has been found to be a rich source of biologically active compounds, especially the broad-spectrum antimicrobial peptides, which have attracted increasing attention as potential therapeutic agents.<br/><br/>In this thesis, a novel bioactive peptide was discovered in the skin secretion of Rana amurensis. This skin secretion was collected by mild electrical stimulation and used to isolate mRNA for the establishment of a cDNA library. “Shotgun” cloning was employed to obtain the peptide precursor-encoding cDNA sequence and the mature peptide structure was deduced from this cloned cDNA. A sufficient quantity of a peptide replicate for bioactivity testing, was synthesised by solid-phase peptide synthesis (SPPS). <br/><br/>After these tests, QUB-2274 was found to exhibit differential growth-inhibitory activity towards the Gram-positive bacterium S.aureus, the Gram-negative bacterium E.coli, and the yeast C.albicans, but with a high haemolytic activity. It also had a strong anti-proliferative effect on the four tested human cancer cell lines: PC-3, NCI-H157, MDA-MB-435S and U251MG.<br/><br/>These studies on QUB-2274, have provided the basic data for research on a bioactive peptide from an amphibian. Unlike conventional antibiotics, the antimicrobial peptides (AMPs) are less likely to cause drug resistance. If QUB-2274 is to be considered for application in the clinic, its high haemolytic activity requires addressing such as by rational analogue design. <br/>","abstract_html":"Based on extensive natural drug investigations, frog skin has been found to be a rich source of biologically active compounds, especially the broad-spectrum antimicrobial peptides, which have attracted increasing attention as potential therapeutic agents.&lt;br/&gt;&lt;br/&gt;In this thesis, a novel bioactive peptide was discovered in the skin secretion of Rana amurensis. This skin secretion was collected by mild electrical stimulation and used to isolate mRNA for the establishment of a cDNA library. “Shotgun” cloning was employed to obtain the peptide precursor-encoding cDNA sequence and the mature peptide structure was deduced from this cloned cDNA. A sufficient quantity of a peptide replicate for bioactivity testing, was synthesised by solid-phase peptide synthesis (SPPS). &lt;br/&gt;&lt;br/&gt;After these tests, QUB-2274 was found to exhibit differential growth-inhibitory activity towards the Gram-positive bacterium S.aureus, the Gram-negative bacterium E.coli, and the yeast C.albicans, but with a high haemolytic activity. It also had a strong anti-proliferative effect on the four tested human cancer cell lines: PC-3, NCI-H157, MDA-MB-435S and U251MG.&lt;br/&gt;&lt;br/&gt;These studies on QUB-2274, have provided the basic data for research on a bioactive peptide from an amphibian. Unlike conventional antibiotics, the antimicrobial peptides (AMPs) are less likely to cause drug resistance. If QUB-2274 is to be considered for application in the clinic, its high haemolytic activity requires addressing such as by rational analogue design. &lt;br/&gt;","abstract_has_math":false,"creators":["Xu, Yiwen"],"institution":"Queen's University Belfast","degree_name":"Master of Philosophy","degree_level":"Masters Thesis","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Chen, Tianbao","Wang, Lei","Zhou, Mei"],"committee_chairs":[],"committee_members":[],"year":2017,"date_issued":"2017","date_published":"2017","updated_at":"2026-07-24T03:54:46Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["oai:pure.qub.ac.uk/portal:studenttheses/7776ef42-e321-4153-b1af-5e78bdb6c681"],"render_values":[{"text":"oai:pure.qub.ac.uk/portal:studenttheses/7776ef42-e321-4153-b1af-5e78bdb6c681","href":null,"code":true}]}]},"links":{"outbound_url":"https://pure.qub.ac.uk/en/studentTheses/7776ef42-e321-4153-b1af-5e78bdb6c681","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Chen, Tianbao","Wang, Lei","Zhou, Mei"]},{"key":"dc:creator","label":"Author","values":["Xu, Yiwen"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2017"]},{"key":"dc:date.issued","label":"Date","values":["2017"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["School of Pharmacy"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["Queen's University Belfast"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["https://pure.qub.ac.uk/en/studentTheses/7776ef42-e321-4153-b1af-5e78bdb6c681"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Masters Thesis"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["Master of Philosophy"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights.embargodate","label":"Dc Rights Embargodate","values":["2022-10-01"]},{"key":"dc:rights.embargoreason","label":"Dc Rights Embargoreason","values":["/dk/atira/pure/core/document/studentthesisembargoreason/publicationissues"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["oai:pure.qub.ac.uk/portal:studenttheses/7776ef42-e321-4153-b1af-5e78bdb6c681","https://pure.qub.ac.uk/en/studentTheses/7776ef42-e321-4153-b1af-5e78bdb6c681"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://pure.qub.ac.uk/files/135449156/The_discovery_of_a_novel_peptide_QUB_2274_from_the_defensive_skin_secretion_of_Rana_amurensis_Yiwen_Xu.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Based on extensive natural drug investigations, frog skin has been found to be a rich source of biologically active compounds, especially the broad-spectrum antimicrobial peptides, which have attracted increasing attention as potential therapeutic agents.<br/><br/>In this thesis, a novel bioactive peptide was discovered in the skin secretion of Rana amurensis. This skin secretion was collected by mild electrical stimulation and used to isolate mRNA for the establishment of a cDNA library. “Shotgun” cloning was employed to obtain the peptide precursor-encoding cDNA sequence and the mature peptide structure was deduced from this cloned cDNA. A sufficient quantity of a peptide replicate for bioactivity testing, was synthesised by solid-phase peptide synthesis (SPPS). <br/><br/>After these tests, QUB-2274 was found to exhibit differential growth-inhibitory activity towards the Gram-positive bacterium S.aureus, the Gram-negative bacterium E.coli, and the yeast C.albicans, but with a high haemolytic activity. It also had a strong anti-proliferative effect on the four tested human cancer cell lines: PC-3, NCI-H157, MDA-MB-435S and U251MG.<br/><br/>These studies on QUB-2274, have provided the basic data for research on a bioactive peptide from an amphibian. Unlike conventional antibiotics, the antimicrobial peptides (AMPs) are less likely to cause drug resistance. If QUB-2274 is to be considered for application in the clinic, its high haemolytic activity requires addressing such as by rational analogue design. <br/>"]},{"key":"dc:title","label":"Title","values":["The discovery of a novel peptide, QUB-2274, from the defensive skin secretion of Rana amurensis"]}]}],"canonical_facts":{"dc:contributor.advisor":["Chen, Tianbao","Wang, Lei","Zhou, Mei"],"dc:creator":["Xu, Yiwen"],"dc:date":["2017"],"dc:date.issued":["2017"],"dc:description.abstract":["Based on extensive natural drug investigations, frog skin has been found to be a rich source of biologically active compounds, especially the broad-spectrum antimicrobial peptides, which have attracted increasing attention as potential therapeutic agents.<br/><br/>In this thesis, a novel bioactive peptide was discovered in the skin secretion of Rana amurensis. This skin secretion was collected by mild electrical stimulation and used to isolate mRNA for the establishment of a cDNA library. “Shotgun” cloning was employed to obtain the peptide precursor-encoding cDNA sequence and the mature peptide structure was deduced from this cloned cDNA. A sufficient quantity of a peptide replicate for bioactivity testing, was synthesised by solid-phase peptide synthesis (SPPS). <br/><br/>After these tests, QUB-2274 was found to exhibit differential growth-inhibitory activity towards the Gram-positive bacterium S.aureus, the Gram-negative bacterium E.coli, and the yeast C.albicans, but with a high haemolytic activity. It also had a strong anti-proliferative effect on the four tested human cancer cell lines: PC-3, NCI-H157, MDA-MB-435S and U251MG.<br/><br/>These studies on QUB-2274, have provided the basic data for research on a bioactive peptide from an amphibian. Unlike conventional antibiotics, the antimicrobial peptides (AMPs) are less likely to cause drug resistance. If QUB-2274 is to be considered for application in the clinic, its high haemolytic activity requires addressing such as by rational analogue design. <br/>"],"dc:identifier":["oai:pure.qub.ac.uk/portal:studenttheses/7776ef42-e321-4153-b1af-5e78bdb6c681","https://pure.qub.ac.uk/en/studentTheses/7776ef42-e321-4153-b1af-5e78bdb6c681"],"dc:identifier.uri":["https://pure.qub.ac.uk/files/135449156/The_discovery_of_a_novel_peptide_QUB_2274_from_the_defensive_skin_secretion_of_Rana_amurensis_Yiwen_Xu.pdf"],"dc:language":["eng"],"dc:publisher.department":["School of Pharmacy"],"dc:publisher.institution":["Queen's University Belfast"],"dc:relation.isreferencedby":["https://pure.qub.ac.uk/en/studentTheses/7776ef42-e321-4153-b1af-5e78bdb6c681"],"dc:rights.embargodate":["2022-10-01"],"dc:rights.embargoreason":["/dk/atira/pure/core/document/studentthesisembargoreason/publicationissues"],"dc:title":["The discovery of a novel peptide, QUB-2274, from the defensive skin secretion of Rana amurensis"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["Masters Thesis"],"dc:type.qualificationname":["Master of Philosophy"]},"updated_at":"2026-07-24T03:54:46Z"}