Selection of mutants of Escherichia coli constitutive for tryptophanase.
نویسندگان
چکیده
Proc. Natl. Acad. Sci. U.S. 40:1064, 1954). The galactose mutations are of the same stability as the streptomycin-sensitivity gene. Some 60 other galactose mutants are similar to those reported in Table 1. No instances of mutability grossly higher than Gal16 or Galg have been noted, and no certain cases of failure to revert have been found. Combinations of Gal mutations have been synthesized via lambda-phage transduction. Such combinations have never been observed to revert, and the combined independent probabilities (ca. 10-2) indicate why this is so.
منابع مشابه
Isolation of Mutants Affecting Tryptophanase Production in Escherichia Coli.
Gartner, Theodore K. (University of California, Davis), and Monica Riley. Isolation of mutants affecting tryptophanase production in Escherichia coli. J. Bacteriol. 89:313-318. 1965.-Mutants of Escherichia coli K-12 were isolated which appear to have suffered an alteration in the regulation system governing tryptophanase synthesis. A novel selection method was used to isolate tryptophanase muta...
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Tryptophanase, encoded by the gene tnaA, is a catabolic enzyme distinct from the enzymes of tryptophan biosynthesis. Tryptophanase synthesis is induced by tryptophan and is subject to catabolite repression. We studied the mechanism of tna operon induction. Mutants with altered rho factor were partially constitutive for tna expression, implicating rho-dependent transcription termination in the c...
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 85 شماره
صفحات -
تاریخ انتشار 1963