{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T13:53:01Z","timestamp":1791553981121,"version":"4.3.4"},"reference-count":24,"publisher":"American Chemical Society (ACS)","issue":"9","license":[{"start":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T00:00:00Z","timestamp":1786492800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T00:00:00Z","timestamp":1786492800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T00:00:00Z","timestamp":1786492800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-045"}],"funder":[{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["F32 AI176709"],"award-info":[{"award-number":["F32 AI176709"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000026","name":"National Institute on Drug Abuse","doi-asserted-by":"publisher","award":["F31 DA060484"],"award-info":[{"award-number":["F31 DA060484"]}],"id":[{"id":"10.13039\/100000026","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000057","name":"National Institute of General Medical Sciences","doi-asserted-by":"publisher","award":["K99 GM158961"],"award-info":[{"award-number":["K99 GM158961"]}],"id":[{"id":"10.13039\/100000057","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000057","name":"National Institute of General Medical Sciences","doi-asserted-by":"publisher","award":["R35 GM118035"],"award-info":[{"award-number":["R35 GM118035"]}],"id":[{"id":"10.13039\/100000057","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000057","name":"National Institute of General Medical Sciences","doi-asserted-by":"publisher","award":["R35 GM143054"],"award-info":[{"award-number":["R35 GM143054"]}],"id":[{"id":"10.13039\/100000057","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,25]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Conversion of cysteine residues to 5-thiooxazole moieties by multinuclear nonheme iron-dependent oxidative enzymes (MNIOs) is a prevalent modification in ribosomally synthesized, post-translationally modified peptide (RiPP) natural products. However, this post-translational modification (PTM) is difficult to distinguish from MNIO-produced oxazolone-coupled thioamides, such as those present in the RiPP methanobactin. The RiPP virulence factor oxazolin contains six copper-binding heterocycles installed by an MNIO. Here, we reassign these PTMs, originally described as oxazolones\/thioamides, as 5-thiooxazoles on the basis of detailed comparative chemical and structural characterization of oxazolin and methanobactin. These data establish a benchmark for differentiating these two PTMs in newly discovered RiPPs.<\/jats:p>","DOI":"10.1021\/acs.jnatprod.6c00701","type":"journal-article","created":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T16:04:24Z","timestamp":1786550664000},"page":"2734-2740","source":"Crossref","is-referenced-by-count":0,"title":["Differentiating 5-Thiooxazoles from Oxazolone-Coupled Thioamides in RiPP Natural Products"],"prefix":"10.1021","volume":"89","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1993-6541","authenticated-orcid":true,"given":"Olivia M.","family":"Manley","sequence":"first","affiliation":[{"name":"Northwestern University , , , ,","place":["Evanston, Illinois, United States, 60208"]},{"name":"Northwestern University , , , ,","place":["Evanston, Illinois, United States, 60208"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-5121-8881","authenticated-orcid":true,"given":"Tucker J.","family":"Shriver","sequence":"additional","affiliation":[{"name":"Northwestern University , , , ,","place":["Chicago, Illinois, United States, 60611"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1738-9919","authenticated-orcid":true,"given":"Jose\u0301 M.","family":"Ayala","sequence":"additional","affiliation":[{"name":"Northwestern University , , , ,","place":["Evanston, Illinois, United States, 60208"]},{"name":"Northwestern University , , , ,","place":["Evanston, Illinois, United States, 60208"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4342-6234","authenticated-orcid":true,"given":"Benjamin C.","family":"Owen","sequence":"additional","affiliation":[{"name":"Northwestern University , , , ,","place":["Evanston, Illinois, United States, 60208"]},{"name":"Northwestern University , , , ,","place":["Evanston, Illinois, United States, 60208"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3740-9999","authenticated-orcid":true,"given":"Joshua J.","family":"Ziarek","sequence":"additional","affiliation":[{"name":"Northwestern University , , , ,","place":["Chicago, Illinois, United States, 60611"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8472-4134","authenticated-orcid":true,"given":"Amy C.","family":"Rosenzweig","sequence":"additional","affiliation":[{"name":"Northwestern University , , , ,","place":["Evanston, Illinois, United States, 60208"]},{"name":"Northwestern University , , , ,","place":["Evanston, Illinois, United States, 60208"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,8,12]]},"reference":[{"key":"2026100909074295500_cit1","doi-asserted-by":"publisher","first-page":"102467","DOI":"10.1016\/j.cbpa.2024.102467","article-title":"Multinuclear non-heme iron dependent oxidative enzymes (MNIOs) involved in unusual peptide modifications","volume":"80","author":"Chen","year":"2024","journal-title":"Curr. 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