Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
16.
Antimicrob Agents Chemother ; 5(1): 68-74, 1974 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-4599795

RESUMEN

Various mutants of an Escherichia coli K-12 strain were prepared, in which a chloramphenicol (CM) resistance gene (cml) derived from an R factor, R100-1, was integrated into the chromosome. The CM acetyltransferase (CATase) activity of these strains and the strain carrying R100-1 were determined during exponential growth with the following results. (i) The CATase activity varied, depending upon the site of integration of the cml gene on the chromosome. Activity was found to be higher when the cml gene was integrated nearer the replication origin of the chromosome, the total enzyme activity found was the sum of activities coded by each gene separately. (iii) When the cml gene was in a cytoplasmic state on an R factor, R100-1, the expressed enzyme activity was four-to eightfold higher than that in the chromosomal state, suggesting the existence of about four to eight copies of R factor per chromosome. The CATase activity returned to the level of that expressed by R100-1 when the chromosomal cml gene was detached and picked up by an R factor.


Asunto(s)
Acetiltransferasas/metabolismo , Cloranfenicol/farmacología , Farmacorresistencia Microbiana , Escherichia coli/enzimología , Genes , Medios de Cultivo , Herencia Extracromosómica , Mutación , Transducción Genética
17.
Kango Gijutsu ; 18(2): 126-34, 1972 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-4481598

Asunto(s)
Ansiedad , Humanos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA