FIG. 1.

Deletion analysis of the TP901-1 promoter region. Numbers refer to the complete TP901-1 genomic sequence present in GenBank under accession number AF304433 (4). The TP901-1 fragments cloned (black lines) indicate a transcriptional fusion to the lacLM genes in pAK80. The specific activities of β-galactosidase of NZ3900 (nisRK) derivatives carrying pMBP22 (orf29) and the indicated plasmids were measured after overnight growth in M17 medium with 0.5% glucose and erythromycin and chloramphenicol (each, 5 μg/ml) in the absence of nisin (−nisin) as well in the presence of nisin (1 ng/ml) (+nisin). Fold, the specific activity of β-galactosidase obtained in the presence of nisin divided by the specific activity of β-galactosidase obtained in the absence of nisin; large black lines, orf genes; small black arrows, mRNA ends identified in primer extension analysis (see Fig. 2).