{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T15:38:51Z","timestamp":1787067531943,"version":"build-2736575974"},"reference-count":47,"publisher":"Oxford University Press (OUP)","license":[{"start":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T00:00:00Z","timestamp":1773187200000},"content-version":"vor","delay-in-days":69,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002657","name":"Istanbul University","doi-asserted-by":"publisher","award":["TDK-2020-36552"],"award-info":[{"award-number":["TDK-2020-36552"]}],"id":[{"id":"10.13039\/501100002657","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,1,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Antimicrobial resistance is a major global health concern that requires innovative therapeutic strategies. This study aimed to address this challenge by designing Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-associated protein (CRISPR-Cas)-based plasmid systems for potential genome editing applications in multidrug-resistant (MDR) Klebsiella pneumoniae clinical isolates. Minimum inhibitory concentrations (MICs) of imipenem, meropenem, and ertapenem were determined according to European Committee on Antimicrobial Susceptibility Testing guidelines. All isolates (n\u00a0=\u00a05) were resistant, with MIC ranges of 4\u2013128\u00a0\u03bcg\/ml for imipenem, 8\u201364\u00a0\u03bcg\/ml for meropenem, and 8\u2013256\u00a0\u03bcg\/ml for ertapenem. Resistance gene analysis revealed blaOXA-48-like and blaCTX-M-15 in all isolates, while blaNDM-1 was detected in one isolate. Two CRISPR-based plasmid systems, CRISPR-Cas9 and CRISPR-assisted cytidine deaminase, were designed. Target genes were amplified by polymerase chain reaction, and guide RNA (gRNA) sequences were designed from selected regions. Apramycin (50\u00a0\u03bcg\/ml) was identified as a suitable selection marker. The pSGKP\u2013AmpR(Pro)\u2013ApmR plasmid was successfully constructed, whereas Cas9 and APOBEC constructs could not be cloned. Overall, this study highlights technical challenges in developing CRISPR-based tools for MDR K. pneumoniae and emphasizes the need for isolate-specific plasmid design and gRNA optimization.<\/jats:p>","DOI":"10.1093\/femsle\/fnag026","type":"journal-article","created":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T12:36:55Z","timestamp":1773146215000},"source":"Crossref","is-referenced-by-count":1,"title":["CRISPR-Cas based plasmid design for multidrug-resistant\n                    <i>Klebsiella pneumoniae<\/i>\n                    isolates"],"prefix":"10.1093","volume":"373","author":[{"given":"Sevinc","family":"Baba","sequence":"first","affiliation":[{"name":"Institute of Health Sciences, Istanbul University Department of Clinical Microbiology, , 34093 Istanbul ,","place":["T\u00fcrkiye"]},{"name":"Life Sciences and Biomedical Engineering Application and Research Centre, Istanbul Gelisim University , 34310 Istanbul 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