2026-10-12T22:03:16Z https://api.figshare.com/v2/oai

oai:figshare.com:article/32641215 2026-10-01T16:24:56Z portal_1172 item_type_8 month_year_10_2026

Identification, modification and functional evaluation of antimicrobial peptides from the skin secretions of Anuran species Baiyu Wang (11215694) PUREID: 640722360 amphibian skin secretions peptide modification cytotoxicity therapeutic index membrane disruption Antimicrobial resistance (AMR) has become one of the most pressing global health challenges, necessitating the development of novel therapeutic agents to replace or supplement traditional antibiotics. Antimicrobial peptides (AMPs), naturally occurring molecules found in various organisms, have emerged as promising alternatives due to their broad-spectrum activity and low susceptibility to resistance development. This study focuses on the identification, modification, and functional evaluation of three AMPs—QUB-2579, QUB-2155, and Brevinin-1-LFc—derived from amphibian skin secretions. These peptides were assessed for their antimicrobial efficacy, cytotoxicity, and structural properties, with modifications designed to optimize their therapeutic window.<br><br>QUB-2579 and Brevinin-1-LFc, both members of the Brevinin-1 family, exhibited significant antimicrobial activity but were hindered by high haemolytic toxicity. Various modifications, including hydrophobicity reduction, were explored to improve their selectivity. While hydrophobicity reduction effectively lowered toxicity in Brevinin-1-LFc, this strategy proved less effective for QUB-2579, suggesting that structural differences and amino acid substitutions influence their functional outcomes. In contrast, QUB-2155 demonstrated strong antimicrobial activity with low haemolysis, making it a promising drug candidate. Increasing its hydrophobicity enhanced antimicrobial efficacy but also raised toxicity, underscoring the challenge of balancing these properties.<br><br>All peptides were found to adopt α-helical structures and exert their effects through membrane disruption, an advantage over conventional antibiotics due to the lower likelihood of resistance development. This study highlights the importance of structural and physicochemical optimization in AMP design. Future work should focus on alternative modification strategies, novel delivery systems, and in vivo validation to advance these peptides toward clinical applications. With further refinement, AMPs have the potential to become next-generation antimicrobial agents in the fight against multidrug-resistant pathogens.<br><br><i>Thesis embargoed until 31st July 2030.</i><br> 2026-10-01T16:24:56Z Text Thesis 10.17034/32641215.v1 https://figshare.com/articles/thesis/Identification_modification_and_functional_evaluation_of_antimicrobial_peptides_from_the_skin_secretions_of_Anuran_species/32641215 All Rights Reserved Open Access after 2030-07-31