Histidine regulation in Salmonella typhimurium. XV. Procedure for the selection of mutants unable to derepress the histidine operon.
نویسندگان
چکیده
A general search has been made for mutants defective in their ability to derepress the histidine operon. The procedure was to select for mutants with an increased sensitivity to the false feedback inhibitor, 2-thiazolealanine. Five mutant strains defective in derepression have been isolated. All five strains are unable to derepress normally because of mutations located in the operator-promoter region of the histidine operon.
منابع مشابه
Histidine Regulatory Mutants in Salmonella typhimurium
Regulation of the histidine operon in Salmonella typhimurium has been shown to involve at least six separate genes (Roth, Antdn & Hartman, 1966; Ant&, 1968). Mutations in any one of these separate genes can destroy the ability of the cell to repress fully the histidine biosynthetic enzymes. In order to understand this regulatory mechanism and the nature of these mutations, we have studied the d...
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عنوان ژورنال:
- Journal of bacteriology
دوره 117 1 شماره
صفحات -
تاریخ انتشار 1974