title: Construction of cys:lac gene fusions in Escherichia coli and their use in the isolation of constitutive cysBc mutants.
abstract: Operon fusions of the lacZ gene to two different genes of the cysteine regulon controlled by the cysB regulatory protein were isolated. The fusion strains were used for selection of cysB constitutive mutants. Three cysBc alleles have been characterized and cloned into multicopy plasmids.
mesh_terms: D003001:Cloning, Molecular; D003545:Cysteine / Q000235:genetics*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005786:Gene Expression Regulation; D005838:Genotype; D007763:Lac Operon; D009154:Mutation
chemical_list: D003545:Cysteine