{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"bioRxiv"}],"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T14:12:43Z","timestamp":1785420763839,"version":"3.56.0"},"posted":{"date-parts":[[2026,3,25]]},"group-title":"Biochemistry","reference-count":37,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T00:00:00Z","timestamp":1774396800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.biorxiv.org\/about\/FAQ#license"}],"funder":[{"award":["R00GM143529"],"award-info":[{"award-number":["R00GM143529"]}],"id":[{"id":"https:\/\/ror.org\/04q48ey07","id-type":"ROR","asserted-by":"publisher"}]},{"award":["R35GM149233"],"award-info":[{"award-number":["R35GM149233"]}],"id":[{"id":"https:\/\/ror.org\/04q48ey07","id-type":"ROR","asserted-by":"publisher"}]},{"award":["3R01GM119374-04S1"],"award-info":[{"award-number":["3R01GM119374-04S1"]}],"id":[{"id":"https:\/\/ror.org\/04q48ey07","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000001","name":"U.S. National Science Foundation","doi-asserted-by":"crossref","award":["1919677"],"award-info":[{"award-number":["1919677"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,3,25]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                <jats:p>\n                  High-valent metal\u2013nitrido species are powerful nitrogen-atom transfer intermediates but remain difficult to access and control due to intrinsic instability and bimolecular N\u2013N coupling pathways. Herein, we report the first formation of a high-valent Mn(V)\u2013nitrido complex within a\n                  <jats:italic>de novo<\/jats:italic>\n                  designed protein scaffold and demonstrate that a reactive precursor to this species can be catalytically intercepted for enantioselective aziridination. A Mn(V)\u2261N unit derived from an abiological diphenyl porphyrin is confined within a designed helical bundle protein, where the protein environment suppresses bimolecular decay and enables detailed spectroscopic characterization. Electron paramagnetic resonance, resonance Raman, and circular dichroism spectroscopies confirm formation of a low-spin Mn(V)\u2013nitrido species that is stable for weeks at room temperature and exhibits minimal perturbation of the Mn\u2261N unit upon modulation of the axial histidine ligand, while catalytic activity and stereochemical outcome are sensitive to its presence. Mechanistic studies identify monochloramine (NH\n                  <jats:sub>2<\/jats:sub>\n                  Cl) as the operative nitrogen-atom donor and support the involvement of a transient Mn-bound N-transfer intermediate en route to nitrido formation. Under catalytic conditions, this intermediate is inter-cepted to perform aziridination with TON \u2248 180 and an enantiomeric ratio of 65:35. Together, these results establish\n                  <jats:italic>de novo<\/jats:italic>\n                  protein design as a platform for stabilizing high-valent metal\u2013nitrido species and harnessing their reactivity for nitrogen-atom transfer chemistry beyond the limits of natural metalloenzymes and small-molecule catalysts.\n                <\/jats:p>","DOI":"10.64898\/2026.03.23.713767","type":"posted-content","created":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T04:27:33Z","timestamp":1774499253000},"source":"Crossref","is-referenced-by-count":0,"title":["Highly Stable Mn(V)-Nitrido and Nitrogen-Atom Transfer Reactivity within a\n                  <i>De Novo<\/i>\n                  Protein"],"prefix":"10.64898","author":[{"given":"Jithin","family":"Thomas","sequence":"first","affiliation":[{"name":"Department of Chemistry, University of California, Riverside, Riverside, CA 91730, United States"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sudha","family":"Yadav","sequence":"additional","affiliation":[{"name":"Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul H.","family":"Oyala","sequence":"additional","affiliation":[{"name":"Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Veronica","family":"Carta","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of California, Riverside, Riverside, CA 91730, United States"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David P.","family":"Goldberg","sequence":"additional","affiliation":[{"name":"Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3392-3170","authenticated-orcid":false,"given":"Samuel I.","family":"Mann","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of California, Riverside, Riverside, CA 91730, United States"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","reference":[{"key":"2026032714053291000_2026.03.23.713767v1.1","first-page":"3592","article-title":"The elusive terminal imido of manganese(V)","volume":"41","year":"2002","journal-title":"Angew. 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