{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T21:26:29Z","timestamp":1789507589743,"version":"build-2803163510"},"reference-count":44,"publisher":"Oxford University Press (OUP)","issue":"7","license":[{"start":{"date-parts":[[2025,7,1]],"date-time":"2025-07-01T00:00:00Z","timestamp":1751328000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,7,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>Co-infections by MDR Acinetobacter baumannii and Klebsiella pneumoniae pose daunting challenges in healthcare settings. This study aimed at investigating the biofilm formation potential of their co-culture and evaluating the effect of combination therapy.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Method<\/jats:title>\n                  <jats:p>Spatial distribution of A. baumannii and K. pneumoniae in co-cultured biofilm was analysed by Confocal Laser Scanning Microscopy (CLSM) with Green Fluorescent Protein (GFP) and mCherry-tagged strains and Field Emission Scanning Electron Microscopy (FESEM). The antibiotic combination was selected through checkerboard assay and its antibiofilm activity was assessed against the co-culture of MDR strains.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>Cell-free supernatant of K. pneumoniae enhanced the planktonic and biofilm growth of A. baumannii. Co-culture of these pathogens revealed interspersed growth in close proximity and significantly higher biofilm than their monocultures (P-value\u00a0&amp;lt;\u00a00.01). Synergistic combination of colistin (MIC\/8) and rifamycin (MIC\/4) at Fractional Inhibitory Concentration (FIC) killed both the pathogens in monoculture within 3\u00a0h. However, the co-culture exhibited enhanced resistance requiring 24\u00a0h for complete eradication. Biofilm formation was inhibited by 77% at 2\u00a0\u00d7\u00a0FIC. Whereas the preformed biofilm was eradicated by 40% at 3\u00a0\u00d7\u00a0FIC (1\/4th of minimum biofilm eradication concentration). CLSM confirmed structural disruption of the biofilm matrix post-treatment at 3\u00a0\u00d7\u00a0FIC, with reduction in biofilm thickness from 7 to 4\u00a0\u00b5m.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusion<\/jats:title>\n                  <jats:p>Acinetobacter baumannii and K. pneumoniae co-exist harmoniously, forming enhanced biofilms in co-cultures. Colistin-rifamycin combination proved highly effective against these dual-species biofilms.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/jambio\/lxaf171","type":"journal-article","created":{"date-parts":[[2025,7,9]],"date-time":"2025-07-09T15:20:46Z","timestamp":1752074446000},"source":"Crossref","is-referenced-by-count":2,"title":["Dual-species biofilm of MDR <i>Acinetobacter baumannii<\/i> and <i>Klebsiella pneumoniae<\/i> are susceptible to colistin-rifamycin combination therapy"],"prefix":"10.1093","volume":"136","author":[{"given":"Vipasha","family":"Thakur","sequence":"first","affiliation":[{"name":"Panjab University Department of Biotechnology, , Chandigarh, 160014 ,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anandita","family":"Chalana","sequence":"additional","affiliation":[{"name":"Panjab University Department of Biotechnology, , Chandigarh, 160014 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