{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T15:51:50Z","timestamp":1781106710549,"version":"3.54.1"},"reference-count":0,"publisher":"National Academy of Sciences","issue":"10","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1977,10]]},"abstract":"<jats:p>\n                    A mutant of\n                    <jats:italic>Escherichia coli<\/jats:italic>\n                    is described that displays kirromycin resistance in a cell-free system by virtue of an altered elongation factor Tu (EF-Tu). In poly(U)-directed poly(Phe) synthesis the kirromycin resistance of the crystallized enzyme ranged between a factor of 80 and 700, depending on temperature. Similarly, kirromycin-induced EF-Tu GTPase activity uncoupled from ribosomes and aminoacyl-tRNA required correspondingly higher concentrations of the antibiotic. Resistance of EF-Tu to kirromycin is a consequence of a modified enzyme structure as indicated by its altered fingerprint pattern.\n                  <\/jats:p>\n                  <jats:p>\n                    P1 transduction experiments showed that the kirromycin-resistant EF-Tu is coded by an altered\n                    <jats:italic>tuf<\/jats:italic>\n                    B gene (\n                    <jats:italic>tuf<\/jats:italic>\n                    B1). The known existence of two genes coding for EF-Tu would interfere with the recognition of a mutant altered in only one of those genes, if the mutation were recessive. Because kirromycin blocks EF-Tu release from the ribosome, kirromycin sensitivity is dominant, as shown by the failure of a mixed EF-Tu population to express resistance\n                    <jats:italic>in vitro<\/jats:italic>\n                    . Therefore, phenotypic expression of kirromycin resistance\n                    <jats:italic>in vivo<\/jats:italic>\n                    appears to be only possible if the EF-Tu mutant lacks an active\n                    <jats:italic>tuf<\/jats:italic>\n                    A gene, a property likely to be inherited from the parental D22 strain. The observations that introduction of a\n                    <jats:italic>tuf<\/jats:italic>\n                    A\n                    <jats:sup>+<\/jats:sup>\n                    region makes the resistant strain sensitive to the antibiotic and that transduction of\n                    <jats:italic>tuf<\/jats:italic>\n                    B1 into a recipient other than\n                    <jats:italic>E. coli<\/jats:italic>\n                    D22 yields kirromycin-sensitive progeny support these conclusions.\n                  <\/jats:p>","DOI":"10.1073\/pnas.74.10.4341","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T03:23:05Z","timestamp":1149045785000},"page":"4341-4345","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":35,"title":["Elongation factor Tu resistant to kirromycin in an\n                    <i>Esherichia coli<\/i>\n                    mutant altered in both\n                    <i>tuf<\/i>\n                    genes"],"prefix":"10.1073","volume":"74","author":[{"given":"Eckhard","family":"Fischer","sequence":"first","affiliation":[{"name":"Ecole Polytechnique, Laboratoire de Biochimie, (Laboratoire associ\u00e9 no 240 du CNRS) F 91128 Palaiseau-Cedex, France"},{"name":"Institut f\u00fcr Biologie II, Lehrbereich Mikrobiologie, Universit\u00e4t T\u00fcbingen, D 7400 T\u00fcbingen, German Federal Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heinz","family":"Wolf","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Biologie II, Lehrbereich Mikrobiologie, Universit\u00e4t T\u00fcbingen, D 7400 T\u00fcbingen, German Federal Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Klaus","family":"Hantke","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Biologie II, Lehrbereich Mikrobiologie, Universit\u00e4t T\u00fcbingen, D 7400 T\u00fcbingen, German Federal Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Parmeggiani","sequence":"additional","affiliation":[{"name":"Ecole Polytechnique, Laboratoire de Biochimie, (Laboratoire associ\u00e9 no 240 du CNRS) F 91128 Palaiseau-Cedex, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1977,10]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.74.10.4341","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T11:00:29Z","timestamp":1649847629000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.74.10.4341"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1977,10]]},"references-count":0,"journal-issue":{"issue":"10","published-print":{"date-parts":[[1977,10]]}},"alternative-id":["10.1073\/pnas.74.10.4341"],"URL":"https:\/\/doi.org\/10.1073\/pnas.74.10.4341","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1977,10]]},"assertion":[{"value":"1977-10-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}