FIG. 3.

(A) The promoter sequences of sed and lac are presented in the top and bottom lines, respectively. The −35, −10, and +1 sequences of the sed promoter are underlined. For the hybrid promoters, dashed lines indicate sed sequences and the indicated bases signify replacement by lac promoter sequences. (B) Activity of mutant forms of the sed promoter. Dashed lines indicate sed sequences, bases indicate base substitutions, and blank spaces indicate deleted bases. CAT assays were conducted with the wild-type (wt) strain KSI2054 harboring the corresponding plasmids. CAT values are expressed as nanomoles of chloramphenicol acetylated per minute per milligram (dry weight) of cells. Average values from three independent determinations and standard deviations are given.