{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T15:29:19Z","timestamp":1787671759779,"version":"build-2736575974"},"reference-count":21,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T00:00:00Z","timestamp":1787616000000},"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":"\n Introduction<\/jats:title>\n \n Animals with intentional genomic alterations (IGAs) hold promise for meeting increasing worldwide demand for animal-source proteins. As part of regulatory risk assessment for introducing animals with IGAs into the food chain, monitoring commensal bacterial microbiota is recommended due to concern that antimicrobial resistance genes used during IGA selection could be transferred, via horizontal gene transfer, to gastrointestinal or environmental bacterial populations, potentially contributing to antimicrobial resistance. The objective of this study was to assess the antimicrobial susceptibility patterns in commensal bacteria isolated from fecal samples of GalSafe\u2122 pigs that have an IGA that includes the aminoglycoside resistance gene\n nptII<\/jats:italic>\n .\n <\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n Antimicrobial resistance rates observed in\n Escherichia coli<\/jats:italic>\n ,\n Salmonella<\/jats:italic>\n ,\n Campylobacter<\/jats:italic>\n and\n Enterococcus<\/jats:italic>\n isolated from GalSafe\u2122 pigs were compared to resistance rates observed in conventional pigs at slaughter. Bacterial isolates were tested for antimicrobial resistance genes by PCR and one isolate underwent whole genome sequencing.\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n In total, 137 bacterial isolates recovered from 55 fecal samples collected from 47 individual adult GalSafe\u2122 pigs were evaluated. Prevalence of antimicrobial resistance in GalSafe\u2122 pigs was generally similar to, or lower than, resistance prevalence reported from conventional pigs at slaughter, based on National Antimicrobial Resistance Monitoring System (NARMS) data. Higher resistance rates in GalSafe\u2122 pigs were observed only for quinolones in\n Campylobacter coli<\/jats:italic>\n (ciprofloxacin and nalidixic acid) and nitrofurantoin in\n Enterococcus<\/jats:italic>\n spp. One isolate (\n E. coli<\/jats:italic>\n ) was positive for\n nptII<\/jats:italic>\n neomycin resistance gene, the same gene used for IGA selection in GalSafe\u2122 pigs, and the remaining 136 isolates were negative for\n nptII<\/jats:italic>\n . However, the positive isolate did not appear to contain nptII derived from the GalSafe\u2122 pig genome as the sequences flanking the gene did not match the IGA.\n <\/jats:p>\n <\/jats:sec>\n \n Discussion<\/jats:title>\n \n We did not detect evidence of\n nptII<\/jats:italic>\n gene transformation into bacterial species of potential human health importance in this population of GalSafe\u2122 pigs.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.3389\/fmicb.2026.1885937","type":"journal-article","created":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T14:50:18Z","timestamp":1787669418000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Antimicrobial susceptibility patterns of commensal fecal bacteria isolated from pigs with an intentional genomic alteration that included the selectable marker gene nptII"],"prefix":"10.3389","volume":"17","author":[{"given":"Tessa E.","family":"LeCuyer","sequence":"first","affiliation":[{"name":"Department of Pathology, Microbiology, and Immunology, UC Davis Weill School of Veterinary Medicine, UC Davis","place":["Davis, CA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeffrey","family":"Monahan","sequence":"additional","affiliation":[{"name":"United Therapeutics Corporation, Department of Xeno R&D","place":["Blacksburg, VA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kayla","family":"Farrell","sequence":"additional","affiliation":[{"name":"United Therapeutics Corporation, Department of Xeno R&D","place":["Blacksburg, VA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kent","family":"Adams","sequence":"additional","affiliation":[{"name":"United Therapeutics Corporation, Department of Xeno R&D","place":["Blacksburg, VA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anneke","family":"Walters","sequence":"additional","affiliation":[{"name":"United Therapeutics Corporation, Department of Xeno R&D","place":["Blacksburg, VA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diamond","family":"McClendon","sequence":"additional","affiliation":[{"name":"Virginia Tech Animal Laboratory Services, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University","place":["Blacksburg, VA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra","family":"Fox","sequence":"additional","affiliation":[{"name":"Virginia Tech Animal Laboratory Services, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University","place":["Blacksburg, VA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John R.","family":"Bianchi","sequence":"additional","affiliation":[{"name":"United Therapeutics Corporation, Department of Xeno R&D","place":["Blacksburg, VA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,25]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"42","DOI":"10.3390\/allergies5040042","article-title":"Alpha-gal syndrome: A concise review.","volume":"5","author":"Cabezas-Cruz","year":"2022","journal-title":"Allergies"},{"key":"B2","volume-title":"Antibiotics Tested by NARMS.","year":"2025"},{"key":"B3","doi-asserted-by":"publisher","first-page":"1109","DOI":"10.1056\/NEJMoa074943","article-title":"Cetuximab-induced anaphylaxis and IgE specific for galactose-alpha-1,3-galactose.","volume":"358","author":"Chung","year":"2008","journal-title":"N. 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