{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T15:12:30Z","timestamp":1791904350926,"version":"4.3.4"},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"2","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1985,6,1]]},"abstract":"<jats:p>Phaseolotoxin, a tripeptide inhibitor of ornithine transcarbamoylase, is a phytotoxin produced by Pseudomonas syringae pv. phaseolicola, the causal agent of halo-blight in beans. In vivo the toxin is cleaved to release N delta-(N'-sulpho-diaminophosphinyl)-L-ornithine, the major toxic chemical species present in diseased leaf tissue. This paper reports on the interaction between N delta-(N'-sulpho-diaminophosphinyl)-L-ornithine and ornithine transcarbamoylase. N delta-(N'-Sulpho-diaminophosphinyl)-L-ornithine was found to be a potent inactivator of the enzyme, in contrast with phaseolotoxin, which previously has been reported to inhibit the enzyme reversibly. Inactivation by N delta-(N'-[35S]sulpho-diaminophosphinyl)-L-ornithine resulted in the incorporation of 35S into ethanol-precipitated protein. The stoicheiometry of 35S incorporation was approximately 1 mol\/mol of active sites. Inactivation was second-order and a rate constant of 10(6) M-1 X s-1 at 0 degree C in 50 mM-Tris\/HCl, pH 9.0, was obtained. Carbamoyl phosphate, a substrate of ornithine transcarbamoylase, protected the enzyme from inactivation. A dissociation constant of 3 microM for the enzyme-carbamoyl phosphate complex was calculated. L-Ornithine, the second substrate for ornithine transcarbamoylase, protected the enzyme only at high concentrations. The results are consistent with N delta-(N'-sulpho-diaminophosphinyl)-L-ornithine being a potent affinity label that binds via the carbamoyl phosphate-binding site of ornithine transcarbamoylase. Cleavage of phaseolotoxin to N delta-(N'-sulpho-diaminophosphinyl)-L-ornithine in vivo appears to be an important function in the physiology of the disease.<\/jats:p>","DOI":"10.1042\/bj2280347","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T20:48:45Z","timestamp":1439239725000},"page":"347-352","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["The inactivation of ornithine transcarbamoylase by <i>N<\/i>\u03b4-(<i>N<\/i>'-sulpho-diaminophosphinyl)-L-ornithine"],"prefix":"10.1042","volume":"228","author":[{"given":"M D","family":"Templeton","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R E","family":"Mitchell","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P A","family":"Sullivan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M G","family":"Shepherd","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/228\/2\/347\/583457\/bj2280347.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/228\/2\/347\/583457\/bj2280347.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,25]],"date-time":"2021-11-25T14:56:06Z","timestamp":1637852166000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/228\/2\/347\/19549\/The-inactivation-of-ornithine-transcarbamoylase-by"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1985,6,1]]},"references-count":0,"journal-issue":{"issue":"2","published-print":{"date-parts":[[1985,6,1]]}},"URL":"https:\/\/doi.org\/10.1042\/bj2280347","relation":{},"ISSN":["0264-6021","1470-8728"],"issn-type":[{"value":"0264-6021","type":"print"},{"value":"1470-8728","type":"electronic"}],"subject":[],"published":{"date-parts":[[1985,6,1]]}}}