{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T14:29:08Z","timestamp":1785421748384,"version":"3.56.0"},"reference-count":18,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T00:00:00Z","timestamp":1783382400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["1R21AI175463-01"],"award-info":[{"award-number":["1R21AI175463-01"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["1R21AI171217-01"],"award-info":[{"award-number":["1R21AI171217-01"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"award":["1R21AI175463-01"],"award-info":[{"award-number":["1R21AI175463-01"]}],"id":[{"id":"https:\/\/ror.org\/01cwqze88","id-type":"ROR","asserted-by":"publisher"}]},{"award":["1R21AI171217-01"],"award-info":[{"award-number":["1R21AI171217-01"]}],"id":[{"id":"https:\/\/ror.org\/01cwqze88","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["MPs"],"abstract":"<jats:p>The pathogenic free-living amoeba Naegleria fowleri is the cause of primary amebic meningoencephalitis (PAM), a central nervous system infection that is almost always lethal. One of the unusual features of the amoebae is the presence of ~4000 copies of a nucleolar-localized closed circular extrachromosomal ribosomal DNA element (CERE) that encodes the cell\u2019s ribosomal RNA repertoire. It has historically been challenging to purify large quantities of CERE, limiting our understanding of the nucleic acid. Here, we describe a methodology for CERE purification that improves yield, reduces processing times, and maintains the integrity of the plasmid. This approach will enable the study of this unique DNA architecture, advancing our understanding of the pathobiology of the organism.<\/jats:p>","DOI":"10.3390\/mps9040105","type":"journal-article","created":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T15:00:32Z","timestamp":1783436432000},"page":"105","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["An Improved Method for the Isolation of Extrachromosomal DNA from the Pathogenic Free-Living Amoeba Naegleria fowleri"],"prefix":"10.3390","volume":"9","author":[{"given":"Colm P.","family":"Roster","sequence":"first","affiliation":[{"name":"Eukaryotic Pathogens Innovation Center, Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2515-5714","authenticated-orcid":false,"given":"James C.","family":"Morris","sequence":"additional","affiliation":[{"name":"Eukaryotic Pathogens Innovation Center, Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e19","DOI":"10.1093\/cid\/ciaa520","article-title":"Epidemiology and clinical characteristics of primary amebic meningoencephalitis caused by Naegleria fowleri: A global review","volume":"73","author":"Gharpure","year":"2021","journal-title":"Clin. 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