{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:54:27Z","timestamp":1785405267895,"version":"3.56.0"},"reference-count":46,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T00:00:00Z","timestamp":1781049600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Science and Technology Council (NSTC), Taiwan","award":["113-2314-B-468-007"],"award-info":[{"award-number":["113-2314-B-468-007"]}]},{"award":["113-2314-B-468-007"],"award-info":[{"award-number":["113-2314-B-468-007"]}],"id":[{"id":"https:\/\/ror.org\/02kv4zf79","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/100019124","name":"Asia University Hospital","doi-asserted-by":"crossref","award":["11451003"],"award-info":[{"award-number":["11451003"]}],"id":[{"id":"10.13039\/100019124","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background\/Objectives: Pseudomonas aeruginosa is a major cause of healthcare-associated infections, and the global rise of multidrug-resistant (MDR) strains has created an urgent need for alternative therapeutics. R- and F-type pyocins are phage tail-like bacteriocins that selectively kill P. aeruginosa by binding to lipopolysaccharide (LPS) receptors. We characterized O-serotype distribution and pyocin susceptibility among clinical isolates from central Taiwan to evaluate their therapeutic potential. Methods: A total of 109 ICU-derived P. aeruginosa isolates were analyzed. O-serotypes were determined by PCR, and pyocin gene carriage was confirmed by sequencing. Purified R1, R2, R5, F1, F2, F4, F7, and F12 pyocins were tested using spot assays. LPS profiles were examined by SDS-PAGE to explore structural correlates of resistance. Synergistic effects of combined R- and F-type pyocins were assessed in MDR isolates. Results: The most prevalent serotypes were O6 (23.9%), O2\/O5\/O16\/O18\/O20 (20.2%), O1 (16.5%), and O11\/O17 (15.6%). Susceptibility was strongly serotype-dependent: O1 and O6 were highly sensitive to both pyocin types, whereas the O2\/O5\/O16\/O18\/O20 group showed marked resistance. SDS-PAGE demonstrated that resistant isolates possessed densely packed long-chain O-antigens, likely shielding LPS core receptors from pyocin binding. F-type pyocins exhibited bactericidal activity comparable to R-types, and R\/F pyocin cocktails produced synergistic killing against MDR isolates. Conclusions: These findings provide an updated serotype profile of P. aeruginosa in Taiwan and highlight the importance of LPS structural variability in pyocin susceptibility. These results underscore the potential of pyocin-based cocktails as a promising precision-medicine strategy to inhibit the planktonic growth and biofilm formation of multidrug-resistant P. aeruginosa isolates.<\/jats:p>","DOI":"10.3390\/antibiotics15060596","type":"journal-article","created":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T02:59:31Z","timestamp":1781146771000},"page":"596","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Synergistic Bactericidal Effects of R- and F-Type Pyocin Cocktails Against Clinical Pseudomonas aeruginosa Isolates from Central Taiwan"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2479-2404","authenticated-orcid":false,"given":"Yi-Luen","family":"Shen","sequence":"first","affiliation":[{"name":"Division of Chest Medicine, Department of Internal Medicine, Asia University Hospital, Asia University, Taichung 413505, Taiwan"},{"name":"Doctoral Program in Translational Medicine, National Chung Hsing University, Taichung 402202, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wen-Tong","family":"Xu","sequence":"additional","affiliation":[{"name":"Graduate Institute of Biochemistry, College of Life Sciences, National Chung Hsing University, Taichung 402202, Taiwan"},{"name":"Taichung Chest Disease Care Association, Taichung 407219, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zih-Ling","family":"Jiang","sequence":"additional","affiliation":[{"name":"Taichung Chest Disease Care Association, Taichung 407219, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0917-0677","authenticated-orcid":false,"given":"Nien-Jen","family":"Hu","sequence":"additional","affiliation":[{"name":"Graduate Institute of Biochemistry, College of Life Sciences, National Chung Hsing University, Taichung 402202, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1337-4127","authenticated-orcid":false,"given":"Ying-Tsong","family":"Chen","sequence":"additional","affiliation":[{"name":"Graduate Institute of Genomics and Bioinformatics, National Chung Hsing University, Taichung 402202, Taiwan"},{"name":"Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli 35053, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7068-1652","authenticated-orcid":false,"given":"Tze-Kiong","family":"Er","sequence":"additional","affiliation":[{"name":"Division of Laboratory Medicine, Asia University Hospital, Asia University, Taichung 413505, Taiwan"},{"name":"Department of Medical Laboratory Science and Biotechnology, Asia University, Taichung 413505, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4251-7038","authenticated-orcid":false,"given":"Chien-Wen","family":"Huang","sequence":"additional","affiliation":[{"name":"Division of Chest Medicine, Department of Internal Medicine, Asia University Hospital, Asia University, Taichung 413505, Taiwan"},{"name":"Department of Medical Laboratory Science and Biotechnology, Asia University, Taichung 413505, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2117","DOI":"10.1007\/s40265-021-01635-6","article-title":"The Epidemiology and Pathogenesis and Treatment of Pseudomonas aeruginosa Infections: An Update","volume":"81","author":"Reynolds","year":"2021","journal-title":"Drugs"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/j.jfma.2011.09.028","article-title":"Antimicrobial drug-resistant microbes associated with hospitalized community-acquired and healthcare-associated pneumonia: A multi-center study in Taiwan","volume":"112","author":"Wu","year":"2013","journal-title":"J. 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