FIG. 3.

β-Galactosidase activity derived from pic and set promoter fusions either in vector pRS551 transformed into EAEC 042 or as single-copy chromosomal integrations in E. coli K-12 strain TE2680. Values are the results of triplicate determination + standard deviation. The plasmids are described in Table 2. The numbers above the inserts refer to nucleotide positions with respect to Fig. 2. pic fusions are expressed from left to right and set fusions from right to left with respect to the lacZ gene. ND, not determined.