FIG. 1.

Protocatechuate catabolism in S. meliloti. (A) The protocatechuate branch of the β-ketoadipate pathway is involved in the catabolism of protocatechuate to intermediates which are funneled into the tricarboxylic acid cycle. β-CM, β-carboxy-cis,cis-muconate; γ-CML, γ-carboxymuconolactone; β-EL, β-ketoadipate enol-lactone. (B) Schematic depiction of the pca genes on the pSymB megaplasmid. Inverted triangles indicate the locations of transposon insertions in S. meliloti strains RmG879 (left triangle) and RmG867 (right triangle).