FIG. 2.

Mapping of the transcription units and the yjjP and yjjQ promoters. (A) Schematic map of the yjjP-yjjQ-bglJ locus. Shown are positions of a riboprobe used in Northern blotting (B) and oligonucleotides S699 and S700 (see Table S2 in the supplemental material) used in the primer extension analyses (C) are indicated. (B) Northern blotting analysis of RNA isolated from the wild-type strain S541 (wt), the Δhns mutant S3346 (hns), and the S541 strain transformed with plasmid pKEDR13 for the expression of LeuO (wt+LeuO) and separated with a denaturing gel, and the blot was hybridized to a riboprobe complementary to the yjjQ RNA. (C) Primer extension mapping of the yjjP promoter and the yjjQ promoter of RNA isolated from the wild-type, the hns mutant, and the wild type expressing LeuO (as in panel B) using the end-labeled oligonucleotides S699 and S700, respectively. The reaction products were separated next to a sequencing ladder generated with the same end-labeled primer. The 5′ end of the yjjP mRNA maps to 113 bases upstream of the yjjP translation start codon, with a second faint signal at 155 bases upstream of yjjP. The 5′ end of the yjjQ mRNA maps to 158 upstream of the yjjQ translation start codon, with a second signal mapping to 172 upstream of the yjjQ promoter codon AUG (Fig. 3).