title: Conditional growth of Escherichia coli caused by expression of vaccinia virus DNA topoisomerase I.
abstract: Active vaccinia virus topoisomerase I is expressed in Escherichia coli containing plasmid p1940 (S. Shuman, M. Golder, and B. Moss, J. Biol. Chem. 263:16401-16407, 1988). Growth curves showed a decline of 2 to 3 logs in the number of viable cells at 42 degrees C after shift from 30 degrees C because of increased vaccinia virus topoisomerase I level. Mutations in the gyrA and gyrB genes allowed cells to grow equally well at 42 and 30 degrees C. The presence of gyrase inhibitor also improved growth at 42 degrees C.
authors.affiliation: Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla 10595.
authors.forename: M E
authors.initials: ME
authors.lastname: Fernandez-Beros
authors.forename: Y C
authors.initials: YC
authors.lastname: Tse-Dinh
mesh_terms: D027081:DNA Gyrase; D004264:DNA Topoisomerases, Type I / Q000096:biosynthesis* / Q000235:genetics; D004250:DNA Topoisomerases, Type II / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics*; D004926:Escherichia coli / Q000254:growth & development*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D014158:Transcription, Genetic; D014616:Vaccinia virus / Q000201:enzymology* / Q000235:genetics
chemical_list: D004279:DNA, Viral; D011994:Recombinant Proteins; D004264:DNA Topoisomerases, Type I; D027081:DNA Gyrase; D004250:DNA Topoisomerases, Type II