FIG. 2.

(A) Schematic diagram of the genomic DNA from M type 1 GAS strain SF370 representing base pairs at ∼1.6 to 1.7 million. The positional relationships of speB, prsA, and spy2040 are represented by filled boxes. Their directions of transcription are indicated by arrows. The positions of putative promoters and terminators are indicated, as are the predicted sizes of the resultant mRNA species. The relative intensities of the resultant transcripts obtained by Northern analysis are indicated by arrows of different thicknesses. The relative positions of the primers used for extension assays for the speB promoter are also given. (B) The nucleotide sequence of this region, covering ropB, speB, and prsA. The open reading frames (ORF) of these genes are boxed, the sequences have been replaced with gene names, and only the first ATG and termination TAG codons are shown. Letters in bold italics represent possible −10 and −35 consensus sequences. Arrows indicate the mapped transcription initiation sites. The two underlined regions are transcription terminators predicted by the TransTerm program. Note that the first predicted terminator, which is for speB, overlaps with the prsA promoter region. (C) Primer extension analyses confirmed the 5′ ends of the speB transcripts.