{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T12:29:16Z","timestamp":1786364956500,"version":"build-2736575974"},"reference-count":35,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,9]],"date-time":"2026-08-09T00:00:00Z","timestamp":1786233600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006769","name":"Russian Science Foundation","doi-asserted-by":"publisher","award":["24-44-02003"],"award-info":[{"award-number":["24-44-02003"]}],"id":[{"id":"10.13039\/501100006769","id-type":"DOI","asserted-by":"publisher"}]},{"award":["24-44-02003"],"award-info":[{"award-number":["24-44-02003"]}],"id":[{"id":"https:\/\/ror.org\/03y2gwe85","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Pseudomonas aeruginosa poses major public health threats, due to its robust, treatment-resistant biofilms, which contribute to multi-drug resistance. Bacteriophages offer a promising alternative. This study evaluates giant Phikzvirus and conventional Pbunavirus phages against pre-formed biofilms from four multi-drug-resistant P. aeruginosa clinical isolates. We tested six phages (three Phikzvirus, three Pbunavirus) against four clinical strains, isolated from chronic urological and pulmonary infections (Ur1, Ur14, Lu3, Lu9) at MOIs 0.001\u20130.1, quantifying biofilm biomass by crystal violet and visualizing architecture by SEM. Phage treatment leads to significant disrupted biofilms in three isolates achieving more than 50% reduction\u2014comparable with typical antibiotic efficacy against mature biofilms. All biofilms retained their EPS architecture after the treatment, as revealed by SEM, suggesting that residual eDNA-polysaccharide complexes could maintain structural cohesion even after bacterial lysis. The phage\u2019s ability to reduce biofilm biomass demonstrated a significant dependence on the multiplicity of infection (MOI). The best results of anti-biofilm activity of phages (reduction in biofilm biomass by more than 75%) were observed for the phage phiKZ for two strains\u2014Ur1 at MOI = 0.001 and Lu9 at MOI = 0.01\u2014and for the phage phi14\/1 for the Ur1 strain at MOI = 0.001. The biofilm formed by the antibiotic-resistant clinical isolate Ur14 demonstrated exceptional resistance to both types of bacteriophages despite the sensitivity of bacteria of this strain to the studied phages. This highlights the need for personalized phage therapy, where tailored phage cocktails are selected for each specific bacterial strain to achieve optimal destruction of the biofilm.<\/jats:p>","DOI":"10.3390\/v18080869","type":"journal-article","created":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T11:38:09Z","timestamp":1786361889000},"page":"869","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Efficacy of Giant Phikz Viruses in Degrading Biofilms of Pseudomonas aeruginosa in Comparison to Pbuna Viruses"],"prefix":"10.3390","volume":"18","author":[{"given":"Yueqi","family":"Wang","sequence":"first","affiliation":[{"name":"Faculty of Biology, Shenzhen MSU-BIT University, 1 International University Park Road, Dayun New Town, Longgang District, Shenzhen 518172, China"},{"name":"Faculty of Biology, Lomonosov Moscow State University, Leninskie Gory 1, Bld 12, Moscow 119234, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3793-1354","authenticated-orcid":false,"given":"Maria","family":"Bourkaltseva","sequence":"additional","affiliation":[{"name":"Mechnikov Research Institute of Vaccines & Sera, Maly Kazenny Side-Street 5a, Moscow 105064, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Burykin","sequence":"additional","affiliation":[{"name":"Mechnikov Research Institute of Vaccines & Sera, Maly Kazenny Side-Street 5a, Moscow 105064, Russia"},{"name":"Lomonosov Institute of Fine Chemical Technologies, MIREA\u2013Russian Technological University, Moscow 119571, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sergey","family":"Krylov","sequence":"additional","affiliation":[{"name":"Mechnikov Research Institute of Vaccines & Sera, Maly Kazenny Side-Street 5a, Moscow 105064, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Pleteneva","sequence":"additional","affiliation":[{"name":"Mechnikov Research Institute of Vaccines & Sera, Maly Kazenny Side-Street 5a, Moscow 105064, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Victor","family":"Krylov","sequence":"additional","affiliation":[{"name":"Mechnikov Research Institute of Vaccines & Sera, Maly Kazenny Side-Street 5a, Moscow 105064, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4678-232X","authenticated-orcid":false,"given":"Olga S.","family":"Sokolova","sequence":"additional","affiliation":[{"name":"Faculty of Biology, Shenzhen MSU-BIT University, 1 International University Park Road, Dayun New Town, Longgang District, Shenzhen 518172, China"},{"name":"Faculty of Biology, Lomonosov Moscow State University, Leninskie Gory 1, Bld 12, Moscow 119234, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1186\/2047-2994-3-32","article-title":"Clinical and economic consequences of hospital-acquired resistant and multidrug-resistant Pseudomonas aeruginosa infections: A systematic review and meta-analysis","volume":"3","author":"Nathwani","year":"2014","journal-title":"Antimicrob. 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