{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T21:06:52Z","timestamp":1780088812738,"version":"3.54.0"},"reference-count":58,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2022,8,17]],"date-time":"2022-08-17T00:00:00Z","timestamp":1660694400000},"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. Cell. Infect. Microbiol."],"abstract":"<jats:p>Bacterial infections with the genus <jats:italic>Enterobacter<\/jats:italic> are notoriously difficult to treat and often associated with resistance to penicillin, aminoglycosides, fluoroquinolones, and third-generation cephalosporins. Also, <jats:italic>Enterobacter<\/jats:italic> species have emerged as the third most common hosts for carbapenemases worldwide, forcing the use of colistin as a \u201clast-resort\u201d antibiotic for the treatment. Studies on the population structure of the genus <jats:italic>Enterobacter<\/jats:italic> repeatedly detect <jats:italic>E. xiangfangensis<\/jats:italic> as a common clinical species present worldwide. Here, we report on the characteristics of an extreme drug-resistant <jats:italic>E. xiangfangensis<\/jats:italic> isolate va18651 (ST88), obtained from a cervical swab of an expectant mother. The isolate was resistant to almost all the classes of antibiotics tested, including \u03b2-lactams (viz., penicillins, carbapenems, cephalosporin, monobactams, and their combinations), quinolone, aminoglycosides, and sulfonamide\/dihydrofolate reductase inhibitor, and exhibited heteroresistance towards colistin. Analysis of its complete genome sequence revealed 37 antibiotic resistance genes (ARGs), including <jats:italic>mcr-9.1<\/jats:italic>, <jats:italic>bla<jats:sub>KPC-2<\/jats:sub><\/jats:italic>, and <jats:italic>bla<jats:sub>OXA-48<\/jats:sub><\/jats:italic>, encoded on three of the four different plasmids (cumulative plasmidome size 604,632 bp). An unusually high number of plasmid-based heavy metal resistance gene (HRG) clusters towards silver, arsenate, cadmium, copper, mercury, and tellurite were also detected. Virulence genes (VGs) for the lipopolysaccharide and capsular polysaccharide structures, iron acquisition (<jats:italic>iroBCDEN<\/jats:italic>, <jats:italic>ent\/fep\/fes<\/jats:italic>, <jats:italic>sitABCD<\/jats:italic>, <jats:italic>iut<\/jats:italic>, and <jats:italic>fur<\/jats:italic>), and a type VI secretion system, together with motility genes and Type IV pili, were encoded chromosomally. Thus, a unique combination of chromosomally encoded VGs, together with plasmid-encoded ARGs and HRGs, converged to result in an extreme drug-resistant, pathogenic isolate with survival potential in environmental settings. The use of a disinfectant, octenidine, led to its eradication; however, the existence of a highly antibiotic-resistant isolate with significant virulence potential is a matter of concern in public health settings and warrants further surveillance for extreme drug-resistant <jats:italic>Enterobacter<\/jats:italic> isolates.<\/jats:p>","DOI":"10.3389\/fcimb.2022.960892","type":"journal-article","created":{"date-parts":[[2022,8,17]],"date-time":"2022-08-17T08:33:10Z","timestamp":1660725190000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":11,"title":["Co-occurrence of dual carbapenemases KPC-2 and OXA-48 with the mobile colistin resistance gene mcr-9.1 in Enterobacter xiangfangensis"],"prefix":"10.3389","volume":"12","author":[{"given":"Yancheng","family":"Yao","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Swapnil","family":"Doijad","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jane","family":"Falgenhauer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Judith","family":"Schmiedel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Can","family":"Imirzalioglu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Trinad","family":"Chakraborty","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2022,8,17]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1186\/1471-2164-12-402","article-title":"BLAST ring image generator (BRIG): Simple prokaryote genome comparisons","volume":"12","author":"Alikhan","year":"2011","journal-title":"BMC Genomics"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.3389\/FMED.2018.00181","article-title":"The vaginal microenvironment: The physiologic role of lactobacilli","volume":"5","author":"Amabebe","year":"2018","journal-title":"Front. 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