title: Blue ghosts: a new method for isolating amber mutants defective in essential genes of Escherichia coli.
abstract: We describe a technique which permits an easy screening for amber mutants defective in essential genes of Escherichia coli. Using this approach, we have isolated three amber mutants defective in the rho gene. An extension of the technique allows the detection of ochre mutants and transposon insertions in essential genes.
mesh_terms: D004926:Escherichia coli / Q000235:genetics* / Q000302:isolation & purification; D005796:Genes; D005821:Genetic Techniques; D009154:Mutation