Regulation of acetohydroxy acid synthase in streptomycin-dependent Escherichia coli.

نویسندگان

  • K J Whitlow
  • W J Polglase
چکیده

Growth of streptomycin-dependent mutants of Escherichia coli K-12 was insensitive to valine when dihydrostreptomycin was present in a nonlimiting concentration in glucose-salts medium. Acetohydroxy acid synthase was derepressed under these conditions, owing to relaxation of catabolite repression. Valine sensitivity and catabolite repression were restored when streptomycin-dependent E. coli K-12 mutants were grown with limiting dihydrostreptomycin. End product repression of acetohydroxy acid synthase under conditions of relaxed catabolite repression was effected by any two (or more) end products except the combination valine plus isoleucine, which caused derepression. Single end products had no detectable effect on acetohydroxy acid synthase formation.

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عنوان ژورنال:
  • Journal of bacteriology

دوره 121 1  شماره 

صفحات  -

تاریخ انتشار 1975