{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T06:14:49Z","timestamp":1788243289777,"version":"build-2803163510"},"reference-count":43,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:p>\n                    The alarming rates at which extensively drug-resistant (XDR) and pandrug-resistant (PDR)\n                    <jats:italic>Enterobacter cloacae<\/jats:italic>\n                    in hospitals are increasing has begun to severely limit treatment options, and thus the urgency for alternative interventions, including bacteriophage therapy. The purpose of the study was to isolate and molecularly characterize phages that can infect\n                    <jats:italic>E. cloacae<\/jats:italic>\n                    , and, furthermore, to assess the antimicrobial efficacy of the four novel lytic bacteriophages (MMRP1, MMRP2, MMRP3, and MMRP4) against antimicrobial-resistant\n                    <jats:italic>E. cloacae<\/jats:italic>\n                    isolates and to evaluate their potential as alternative therapeutic strategies. These novel phages were characterized by plaque morphology, transmission electron microscopy (TEM), host range testing, thermal and chloroform stability assays, bacterial reduction assays, and whole-genome sequencing (WGS). Among 27 clinical isolates, MDR, XDR, and PDR phenotypes were observed in 20 (74.1%), six (22.2%), and one (3.7%) isolates, respectively. All four phages produced clear lytic plaques (0.5\u20133.0\u202fmm) with titers reaching up to 6\u202f\u00d7\u202f10\n                    <jats:sup>10<\/jats:sup>\n                    PFU\/mL, and the phage cocktail lysed 81.4% (22 of 27 isolates) of clinical isolates with high host specificity. TEM revealed that all four\n                    <jats:italic>E. cloacae<\/jats:italic>\n                    -infecting phages (MMRP1, MMRP2, MMRP3, and MMRP4) belong to the class\n                    <jats:italic>Caudoviricetes<\/jats:italic>\n                    , exhibiting icosahedral capsids, tailed morphology, and double-stranded DNA genomes, consistent with current ICTV classification criteria. Whole genome sequencing and comparative phylogenetic analysis further resolved the taxonomic placement of these phages at the family level, positioning MMRP1 within the family\n                    <jats:italic>Demerecviridae<\/jats:italic>\n                    and MMRP4 within the family\n                    <jats:italic>Straboviridae<\/jats:italic>\n                    . All phages were stable from \u221220 to 40\u202f\u00b0C and were unaffected by exposure to chloroform. Phage cocktail reduced bacterial OD\u2086\u2080\u2080 to \u2264 0.3 within 4\u202fh in the bacterial reduction test. WGS revealed large circular dsDNA genomes of ~132 kbp (MMRP1) and ~149 kbp (MMRP4), GC content of 38%, and modular architectures encoding structural, lytic, and replication gene modules. The most striking and highlighted suggestion that\n                    <jats:italic>in vitro<\/jats:italic>\n                    evaluation of MMRP1 and MMRP4 are highly recommended to more deeper future experimental studies to combat MDR\n                    <jats:italic>E. cloacae<\/jats:italic>\n                    nosocomial infections supported by genomic foundation and eventually, the possibility to be suitable for phage-engineering applications in clinical settings.\n                  <\/jats:p>","DOI":"10.3389\/fmicb.2026.1838809","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T05:33:22Z","timestamp":1788240802000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Genomic and functional characterization of novel therapeutic lytic bacteriophages targeting multidrug-resistant Enterobacter cloacae"],"prefix":"10.3389","volume":"17","author":[{"given":"Mohammad S. A.","family":"Al-Obaidi","sequence":"first","affiliation":[{"name":"Anbar Health Directorate, Department of Inspection, Anbar Governorate","place":["Ramadi, Iraq"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mushtak T. S.","family":"Al-Ouqaili","sequence":"additional","affiliation":[{"name":"Department of Microbiology, College of Medicine, University of Anbar, Anbar Governorate","place":["Ramadi, Iraq"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Farah","family":"Al-Marzooq","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, College of Medicine and Health Sciences, United Arab Emirates University","place":["Al-Ain, United Arab Emirates"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,1]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"70","DOI":"10.3390\/v9040070","article-title":"How to name and classify your phage: an informal guide","volume":"9","author":"Adriaenssens","year":"2017","journal-title":"Viruses"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"1588446","DOI":"10.3389\/fcimb.2025.1588446","article-title":"Harnessing bacterial immunity: CRISPR-Cas system as a versatile tool in combating pathogens and revolutionizing medicine","volume":"15","author":"Al-Ouqaili","year":"2025","journal-title":"Front. 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