FIG 6.

Effect of replacements of a pair of conserved aspartate residues on ArgO function. (A) Samples of 5 μl of 10,000-fold-diluted stationary-phase cultures of GJ4823 bearing the vector or plasmid pHYD2835 encoding C-terminally HA-tagged ArgO and its plasmid derivatives encoding ArgO with the amino acid substitutions indicated were spotted onto the surface of an MA agar plate (I) and an MA agar plate containing 2 μg/ml Can (II). (B) Levels of substitution-bearing ArgO proteins detected by immunoblotting with anti-HA antibody. Sample loading was done as described in the legend to Fig. 5, and the ArgO-encoding plasmids indicated are described in Table S1 in the supplemental material.