{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,16]],"date-time":"2026-08-16T13:26:00Z","timestamp":1786886760105,"version":"build-2736575974"},"reference-count":0,"publisher":"Knowledge E DMCC","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJM"],"abstract":"<jats:p>Background and Objectives: Flavoprotein monooxygenases (FPMOs) participate in various biological processes, includ- ing lignin degradation, natural product biosynthesis, and xenobiotic detoxification. This study aimed to investigate the heter- ologous expression of FPMO and assess its functional activity by examining its capacity to inactivate ampicillin.\r\nMaterials and Methods: In silico analyses were performed to predict the enzyme's secondary and tertiary structures. The target gene was isolated from Pseudomonas aeruginosa, cloned into the pET-22b vector, and expressed in Escherichia coli BL21 (DE3). Heterologous protein expression was examined using SDS\u2013PAGE, and the protein was purified through nickel-affinity chromatography. Enzymatic activity was measured by spectrophotometric monitoring of NADPH oxidation at 340 nm. Antibacterial activity was tested using an agar well-diffusion assay, measuring the inhibition zone diameter in E. coli treated with ampicillin.\r\nResults: Homology modeling indicated that the 3D structure of FPMO is very similar to cyclohexanone monooxygenase, supporting its classification as a Baeyer\u2013Villiger monooxygenase (BVMO). Molecular docking proposed that ampicillin might be a substrate for FPMO, with predicted interactions at Ile141 and Val159. Enzymatic assays confirmed that FPMO catalyzes the oxidation of ampicillin, using FAD and NADPH as cofactors. Additionally, well-diffusion tests showed de- creased ampicillin antibacterial activity after treatment. The enzyme's activity was further confirmed using an ampicillin inactivation assay.\r\nConclusion: The heterologously expressed protein was functionally active. These findings suggest that the studied FPMO may play a role in antibiotic resistance in P. aeruginosa by oxidatively inactivating ampicillin.\r\n\u00a0<\/jats:p>","DOI":"10.18502\/ijm.v18i4.22196","type":"journal-article","created":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T12:18:09Z","timestamp":1785759489000},"source":"Crossref","is-referenced-by-count":0,"title":["Surveying a Pseudomonas aeruginosa-derived oxidoreductase activity"],"prefix":"10.18502","author":[{"given":"Maliheh","family":"Mohammadkhani","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shamsozoha","family":"Abolmaali","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shakiba Darvishalipour","family":"Astaneh","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"7770","published-online":{"date-parts":[[2026,8,3]]},"container-title":["Iranian Journal of Microbiology"],"original-title":[],"link":[{"URL":"https:\/\/publish.kne-publishing.com\/index.php\/IJM\/article\/download\/22196\/20629","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/publish.kne-publishing.com\/index.php\/IJM\/article\/download\/22196\/20629","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,16]],"date-time":"2026-08-16T13:09:30Z","timestamp":1786885770000},"score":1,"resource":{"primary":{"URL":"https:\/\/publish.kne-publishing.com\/index.php\/IJM\/article\/view\/22196"},"secondary":[{"URL":"https:\/\/ijm.tums.ac.ir\/index.php\/ijm\/article\/view\/4421","label":"UNIVERSITY"}]},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,3]]},"references-count":0,"URL":"https:\/\/doi.org\/10.18502\/ijm.v18i4.22196","relation":{},"ISSN":["2008-4447","2008-3289"],"issn-type":[{"value":"2008-4447","type":"electronic"},{"value":"2008-3289","type":"print"}],"subject":[],"published":{"date-parts":[[2026,8,3]]}}}