FIG. 2.

Genetic and physical organization of the CB pathway genes of strain JS705. (A) The upper line shows the relative positions of the aromatic ring dioxygenase gene cluster (mcb) and the genes for chlorocatechol degradation (clc) and their orientations (as determined by DNA sequencing). Below this are the approximate locations of the primer sets used (Table 3). Restriction site abbreviations: P, PstI; E, EcoRI; S, SalI; B, BamHI; X, XhoI; H, HindIII. At the bottom the cloned fragments of the region and the plasmid designations are indicated. (B) Initial enzymatic steps in the degradation of CB and toluene. The initial dioxygenation and rearomatization steps in toluene degradation are carried out by enzymes which can also mediate CB conversion.