FIG. 2.

Growth capacities of M. loti catalase mutants on solid medium in the presence of H₂O₂. Catalase mutants and their derivatives were subjected to an inhibition zone assay for H₂O₂ sensitivity, as described in Materials and Methods. The strains used were the wild type (WT), MAFF303099; katE, ML2101D; katE/c086, ML2101D harboring cosmid c086 that contained the katE gene; katG, ML6940DS; katG/c279, ML6940DS harboring cosmid c279 that contained the katG gene; and katE katG, MLDKAT. The data represent the means of at least four independent experiments, and the error bars indicate standard deviations.