A multisite-mutation map of the leucine operon of Salmonella typhimurium.
نویسندگان
چکیده
LEUCINE is synthesized in Salmonella typhimurium by the pathway shown in Figure 3 (BURNS, UMBARGER and GROSS 1963). The genes specifying the leucine-forming enzymes are clustered in one region of the genome between ara and azi and comprise an operon (MARGOLIN 1963; BURNS, CALVO, MARGOLIN and UMBARGER 1966; CALVO, MARGOLIN and UMBARGER 1969). We describe here the isolation and characterization of a large number of leucine auxotrophs and the construction of a detailed multisite-mutation map of the leucine operon.
منابع مشابه
Operator constitutive mutations in the leucine operon of Salmonella typhimurium.
N a previous communication (CALVO, FREUNDLICH and UMBARGER 1969), a I group of Salmonella typhimurium mutants was described as having the following properties. They were resistant to an analog of leucine, 5’,5’,5’-trifluoroDL-leucine (RENNERT and ANKER 1963), excreted leucine, had constitutive and derepressed levels of enzymes involved in leucine biosynthesis, and they had mutant sites linked t...
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عنوان ژورنال:
- Genetics
دوره 64 2 شماره
صفحات -
تاریخ انتشار 1970