{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T00:59:54Z","timestamp":1768784394023,"version":"3.49.0"},"reference-count":54,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,21]],"date-time":"2023-01-21T00:00:00Z","timestamp":1674259200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\/MCTES\u2014Portuguese Foundation for Science and Technology","award":["CIRCNA\/BRB\/0281\/2019"],"award-info":[{"award-number":["CIRCNA\/BRB\/0281\/2019"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Membranes"],"abstract":"<jats:p>Cationic antimicrobial peptides (CAMPs) offer a promising strategy to counteract bacterial resistance, mostly due to their membrane-targeting activity. W-BP100 is a potent broad-spectrum cecropin-melittin CAMP bearing a single N-terminal Trp, which was previously found to improve its antibacterial activity. W-BP100 has high affinity toward anionic membranes, inducing membrane saturation at low peptide-to-lipid (P\/L) ratios and membrane permeabilization, with the unique property of promoting the aggregation of anionic vesicles only at specific P\/L ratios. Herein, we aimed to investigate this unusual behavior of W-BP100 by studying its aggregation and fusion properties with negatively-charged large (LUVs) or giant (GUVs) unilamellar vesicles using biophysical tools. Circular dichroism (CD) showed that W-BP100 adopted an \u03b1-helical conformation in anionic LUVs, neutralizing its surface charge at the aggregation P\/L ratio. Its fusion activity, assessed by F\u00f6rster resonance energy transfer (FRET) using steady-state fluorescence spectroscopy, occurred mainly at the membrane saturation\/aggregation P\/L ratio. Confocal microscopy studies confirmed that W-BP100 displays aggregation and detergent-like effects at a critical P\/L ratio, above which it induces the formation of new lipid aggregates. Our data suggest that W-BP100 promotes the aggregation and fusion of anionic vesicles at specific P\/L ratios, being able to reshape the morphology of GUVs into new lipid structures.<\/jats:p>","DOI":"10.3390\/membranes13020138","type":"journal-article","created":{"date-parts":[[2023,1,23]],"date-time":"2023-01-23T01:36:26Z","timestamp":1674437786000},"page":"138","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["The Unusual Aggregation and Fusion Activity of the Antimicrobial Peptide W-BP100 in Anionic Vesicles"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4837-0700","authenticated-orcid":false,"given":"Ana Rita","family":"Ferreira","sequence":"first","affiliation":[{"name":"LAQV\/REQUIMTE (Laborat\u00f3rio Associado para a Qu\u00edmica Verde\u2014Rede de Qu\u00edmica e Tecnologia), Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, Rua do Campo Alegre, s\/n, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9907-9518","authenticated-orcid":false,"given":"Mariana","family":"Ferreira","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE (Laborat\u00f3rio Associado para a Qu\u00edmica Verde\u2014Rede de Qu\u00edmica e Tecnologia), Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, Rua do Campo Alegre, s\/n, 4169-007 Porto, Portugal"}]},{"given":"Cl\u00e1udia","family":"Nunes","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE, Laborat\u00f3rio de Qu\u00edmica Aplicada, Faculdade de Farm\u00e1cia da Universidade do Porto, Portugal, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0736-2835","authenticated-orcid":false,"given":"Salette","family":"Reis","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE, Laborat\u00f3rio de Qu\u00edmica Aplicada, Faculdade de Farm\u00e1cia da Universidade do Porto, Portugal, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]},{"given":"C\u00e1tia","family":"Teixeira","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE (Laborat\u00f3rio Associado para a Qu\u00edmica Verde\u2014Rede de Qu\u00edmica e Tecnologia), Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, Rua do Campo Alegre, s\/n, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6018-4724","authenticated-orcid":false,"given":"Paula","family":"Gomes","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE (Laborat\u00f3rio Associado para a Qu\u00edmica Verde\u2014Rede de Qu\u00edmica e Tecnologia), Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, Rua do Campo Alegre, s\/n, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4747-6853","authenticated-orcid":false,"given":"Paula","family":"Gameiro","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE (Laborat\u00f3rio Associado para a Qu\u00edmica Verde\u2014Rede de Qu\u00edmica e Tecnologia), Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, Rua do Campo Alegre, s\/n, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Holmes, E.A.F., and Hughes, D.A. 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