Molecular cloning, structural characterisation and functional study of peptides from amphibian skin secretion
type: CreativeWork
description: The skin secretions of amphibians contain large amounts of biologically-active compounds, such as antimicrobial peptides (AMPs), anticancer peptides and trypsin inhibitors. Several kinds of AMPs, isolated and characterised from the skin of amphibians, have been studied by researchers to provide novel kinds of drugs and pharmacological agents for humans to treat diseases. In this study, the skin secretions of the Chinese Piebald Odorous Frog (Odorrana schmackeri) and the European Edible Frog (Pelophylax kl. esculentus) were collected using an electrical stimulation method. Afterwards, three novel peptide (bombesin-OS, bombesin-PE and QUB2455) sequences were deduced from cDNAs and then confirmed by high performance liquid chromatography (HPLC) and tandem mass spectrometry (MS/MS). The pharmacological effects of bombesin-OS and bombesin-PE were tested. In addition, the antimicrobial activity and antibiofilm activity of AMPs were assessed and their haemolysis activity was also tested. Apart from these, the relationship between structure and function of AMPs was determined by means of CD experiments and secondary structure predictions. Moreover, the antimicrobial activity mechanism of AMPs was evaluated. In Chapter 3, the effects of bombesin-OS and bombesin-PE on smooth muscle were determined in bladder, uterus, and ileum. Both bombesin-OS and bombesin-PE possessed significant contractile activity on bladder, uterus and ileum. In Chapter 4, QUB2455 was found to exhibit strong bactericidal activity especially against Gram-positive organisms. Moreover, our results revealed that QUB2455 demonstrated strong antimicrobial activity against MRSA and E. faecalis. Additionally, QUB2455 showed low cytotoxicity against horse blood erythrocytes and cancer cells. It also possessed a higher TI value than ampicillin. The time-killing against MRSA of QUB2455 illustrated that QUB2455 could kill MRSA rapidly. In addition, QUB2455 possessed strong antibiofilm ability against S. aureus, MRS…
abstract: The skin secretions of amphibians contain large amounts of biologically-active compounds, such as antimicrobial peptides (AMPs), anticancer peptides and trypsin inhibitors. Several kinds of AMPs, isolated and characterised from the skin of amphibians, have been studied by researchers to provide novel kinds of drugs and pharmacological agents for humans to treat diseases. In this study, the skin secretions of the Chinese Piebald Odorous Frog (Odorrana schmackeri) and the European Edible Frog (Pelophylax kl. esculentus) were collected using an electrical stimulation method. Afterwards, three novel peptide (bombesin-OS, bombesin-PE and QUB2455) sequences were deduced from cDNAs and then confirmed by high performance liquid chromatography (HPLC) and tandem mass spectrometry (MS/MS). The pharmacological effects of bombesin-OS and bombesin-PE were tested. In addition, the antimicrobial activity and antibiofilm activity of AMPs were assessed and their haemolysis activity was also tested. Apart from these, the relationship between structure and function of AMPs was determined by means of CD experiments and secondary structure predictions. Moreover, the antimicrobial activity mechanism of AMPs was evaluated. In Chapter 3, the effects of bombesin-OS and bombesin-PE on smooth muscle were determined in bladder, uterus, and ileum. Both bombesin-OS and bombesin-PE possessed significant contractile activity on bladder, uterus and ileum. In Chapter 4, QUB2455 was found to exhibit strong bactericidal activity especially against Gram-positive organisms. Moreover, our results revealed that QUB2455 demonstrated strong antimicrobial activity against MRSA and E. faecalis. Additionally, QUB2455 showed low cytotoxicity against horse blood erythrocytes and cancer cells. It also possessed a higher TI value than ampicillin. The time-killing against MRSA of QUB2455 illustrated that QUB2455 could kill MRSA rapidly. In addition, QUB2455 possessed strong antibiofilm ability against S. aureus, MRS…
author: Zhou, Xiaowei
language: eng
date published: 2019-7
date modified: 2026-07-24T03:54:59Z
provider: Queen's University Belfast
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Queen's University Belfast