{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T18:09:11Z","timestamp":1788890951292,"version":"build-2803163510"},"reference-count":32,"publisher":"Public Library of Science (PLoS)","issue":"9","license":[{"start":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T00:00:00Z","timestamp":1788825600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["23H00446"],"award-info":[{"award-number":["23H00446"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>\n                    In this study, we investigated the prevalence and abundance of the mercury resistance gene\n                    <jats:italic>merA<\/jats:italic>\n                    in human feces, retail chicken meat, and environmental water samples collected from Japan, Vietnam, and Ghana. A real-time PCR assay developed in this study demonstrated high specificity toward\n                    <jats:italic>merA<\/jats:italic>\n                    sequences from more than 12 bacterial species. Using this assay,\n                    <jats:italic>merA<\/jats:italic>\n                    was detected in 6.8% of human fecal samples in Japan (n\u2009=\u200929), in contrast to significantly higher rates observed in Vietnam (70.2%, n\u2009=\u200947) and Ghana (97.4%, n\u2009=\u200939). Similar geographic trends were evident in the chicken meat samples: 18.5% in Japan (n\u2009=\u200927), 66% in Vietnam (n\u2009=\u200991), and 90% in Ghana (n\u2009=\u200910). Environmental water samples showed a consistently high\n                    <jats:italic>merA<\/jats:italic>\n                    detection rate across all countries (75\u2013100%, n\u2009=\u200921), with substantially higher gene copy numbers in Vietnam and Ghana than in Japan.\n                    <jats:italic>merA<\/jats:italic>\n                    was detected in some water samples, even when total mercury concentrations were below the detection limit, indicating that molecular detection may offer greater sensitivity than traditional physicochemical methods. Mercury-resistant bacteria were successfully isolated and cultured, and\n                    <jats:italic>Citrobacter freundii<\/jats:italic>\n                    was identified as the representative strain. Genomic analysis revealed that\n                    <jats:italic>merA<\/jats:italic>\n                    was located on an IncFIB plasmid, flanked by insertion sequences, suggesting its potential for horizontal gene transfer. These findings highlight\n                    <jats:italic>merA<\/jats:italic>\n                    as a promising biomarker for environmental mercury exposure and support the utility of fecal\n                    <jats:italic>merA<\/jats:italic>\n                    analysis as a proxy for assessing mercury-related public health risks.\n                  <\/jats:p>","DOI":"10.1371\/journal.pone.0357976","type":"journal-article","created":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T17:41:21Z","timestamp":1788889281000},"page":"e0357976","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Comparative prevalence of the mercury resistance gene merA in human feces, food, and environmental water from Japan, Vietnam, and Ghana"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8630-8350","authenticated-orcid":true,"given":"Yen Hai","family":"Le","sequence":"first","affiliation":[{"name":"The United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University","place":["Gifu, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Judith Dzifa","family":"Azumah","sequence":"additional","affiliation":[{"name":"The United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University","place":["Gifu, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diep Thi","family":"Khong","sequence":"additional","affiliation":[{"name":"Center for Medical and Pharmaceutical Research and Service, Thai Binh University of Medicine and Pharmacy","place":["Hung Yen, Vietnam"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thang Nam","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Center for Medical and Pharmaceutical Research and Service, Thai Binh University of Medicine and Pharmacy","place":["Hung Yen, Vietnam"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4012-2566","authenticated-orcid":true,"given":"Cornelia","family":"Appiah-Kwarteng","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University of Ghana","place":["Accra, Ghana"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1563-3308","authenticated-orcid":true,"given":"Kazuaki","family":"Matsui","sequence":"additional","affiliation":[{"name":"Kindai University","place":["Higashi-Osaka, Japan"],"department":["Department of Civil and Environmental Engineering"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5603-6825","authenticated-orcid":true,"given":"Mayumi","family":"Yamamoto","sequence":"additional","affiliation":[{"name":"The United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University","place":["Gifu, Japan"]},{"name":"Health Administration Center, Gifu University","place":["Gifu, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaori","family":"Tanaka","sequence":"additional","affiliation":[{"name":"The United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University","place":["Gifu, Japan"]},{"name":"Institute for Glyco-core Research, Gifu University","place":["Gifu, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2942-1672","authenticated-orcid":true,"given":"Yoshimasa","family":"Yamamoto","sequence":"additional","affiliation":[{"name":"The United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University","place":["Gifu, 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