{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T15:49:01Z","timestamp":1781106541591,"version":"3.54.1"},"reference-count":0,"publisher":"National Academy of Sciences","issue":"12","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1971,12]]},"abstract":"<jats:p>\n                    Earlier studies showed that two protein components, P\n                    <jats:sub>I<\/jats:sub>\n                    and P\n                    <jats:sub>II<\/jats:sub>\n                    , are concerned with the adenylylation and deadenylylation of\n                    <jats:italic>Escherichia coli<\/jats:italic>\n                    glutamine synthetase (EC 6.3.1.2). P\n                    <jats:sub>I<\/jats:sub>\n                    by itself catalyzes both adenylylation and deadenylylation, but its activity is modulated by the P\n                    <jats:sub>II<\/jats:sub>\n                    -protein and by glutamine, 2-oxoglutarate, ATP, and UTP, The P\n                    <jats:sub>II<\/jats:sub>\n                    -protein exists in two forms: one form, P\n                    <jats:sub>II<\/jats:sub>\n                    -AT, stimulates P\n                    <jats:sub>I<\/jats:sub>\n                    -catalyzed adenylylation activity in the absence of glutamine and makes this activity very sensitive to inhibition by 2-oxoglutarate; it does not affect deadenylylation activity. The other form, P\n                    <jats:sub>II<\/jats:sub>\n                    -DA, stimulates adenylylation only if glutamine is present, and also stimulates the deadenylylation activity of P\n                    <jats:sub>I<\/jats:sub>\n                    , which is then dependent upon the presence of ATP and 2-oxoglutarate. Conversion of P\n                    <jats:sub>II<\/jats:sub>\n                    -AT to P\n                    <jats:sub>II<\/jats:sub>\n                    -DA requires the presence of UTP, ATP, and 2-oxoglutarate; it is catalyzed by an enzyme present in P\n                    <jats:sub>I<\/jats:sub>\n                    preparations. UTP may be directly involved in this conversion since P\n                    <jats:sub>II<\/jats:sub>\n                    -DA fractions reisolated by filtration through Sephadex G-100 contain small quantities of a bound uridine derivative that lacks the \u03b3-phosphoryl group of UTP. The activity of P\n                    <jats:sub>II<\/jats:sub>\n                    -DA, but not of P\n                    <jats:sub>II<\/jats:sub>\n                    -AT, is destroyed by treatment with snake-venom phosphodiesterase. ATP and 2-oxoglutarate apparently function as allosteric effectors for the conversion of P\n                    <jats:sub>II<\/jats:sub>\n                    -AT to P\n                    <jats:sub>I<\/jats:sub>\n                    -DA.\n                  <\/jats:p>","DOI":"10.1073\/pnas.68.12.2949","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T02:27:16Z","timestamp":1149042436000},"page":"2949-2953","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":127,"title":["Modulation of Glutamine Synthetase Adenylylation and Deadenylylation Is Mediated by Metabolic Transformation of the P\n                    <sub>II<\/sub>\n                    -Regulatory Protein"],"prefix":"10.1073","volume":"68","author":[{"given":"M. S.","family":"Brown","sequence":"first","affiliation":[{"name":"Laboratory of Biochemistry, Section on Enzymes, National Heart and Lung Institute, NIH, Bethesda, Maryland 20014"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A.","family":"Segal","sequence":"additional","affiliation":[{"name":"Laboratory of Biochemistry, Section on Enzymes, National Heart and Lung Institute, NIH, Bethesda, Maryland 20014"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"E. R.","family":"Stadtman","sequence":"additional","affiliation":[{"name":"Laboratory of Biochemistry, Section on Enzymes, National Heart and Lung Institute, NIH, Bethesda, Maryland 20014"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1971,12]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.68.12.2949","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T10:35:33Z","timestamp":1649846133000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.68.12.2949"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1971,12]]},"references-count":0,"journal-issue":{"issue":"12","published-print":{"date-parts":[[1971,12]]}},"alternative-id":["10.1073\/pnas.68.12.2949"],"URL":"https:\/\/doi.org\/10.1073\/pnas.68.12.2949","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1971,12]]},"assertion":[{"value":"1971-12-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}