The identification, modification and functional assessment of three novel bioactive peptides from the defensive skin secretion of Rana genus frogs

This research contained three experimental chapters. Based on the experimental results, the first peptide, QUB-1986, and the modified peptide, 2170-2R, were demonstrated to have increased antibacterial action when used in conjunction with antibiotics, as well as an inhibitory effect on various resistant P. aeruginosa strains in the first section. The second peptide, Hejiangin-B1, was modified in the second portion by the addition of hydrophobic amino acids to boost antibacterial action, indicating the effect of hydrophobicity on peptide activity, and by cyclisation to improve peptide stability in salt ion and enzyme environments.

The third portion primarily focused on the antimicrobial action of peptides in various acidic environments, with the study's fundamental rationale being to adjust the overall charge number of the peptide utilising the variation in pH.<br><br><i>Thesis is embargoed until 31 July 2029.</i>