GLUTAMYL-GAMMA-METHYL ESTER ACTS AS A METHIONINE ANALOG IN ESCHERICHIA-COLI ANALOG RESISTANT MUTANTS MAP AT THE METJ AND METK LOCI

Escherichia coli K-12 mutants resistant to glutamyl-γ-methyl ester were isolated. A mutation leading to resistance of up to 1·4 mg/ml of the methionine analogue maps at min 63 and is 13% cotransducible with serA indicating an alteration in the metK gene. Another mutation leading to resistance to 3 mg/ml of the analogue and cross-resistance to other amino acid analogues maps at min 87. This mutation, which has the phenotype of MetJ−, is shown to be situated between the glpK and metB genes and thus indicates a different gene order from the published one. © 1979, Cambridge University Press. All rights reserved.