FIG. 4.

Transcription initiation point of the davD promoter and key sequence features in the proximal 5′ region. (A) Transcription initiation mapping of the davD gene. Lane 1, RNA isolated from cells grown on M9 minimal medium with 5 mM lysine. The other lanes correspond to a sequencing ladder. The DNA sequence corresponding to the davD promoter region is shown on the left. The transcription start point is in boldface and is marked +1. The proposed −10 box is in boldface. (B) Organization of the davD promoter region. The −10 and −35 regions are indicated in boldface and by gray boxes. A T-rich region is shown in an open box. Convergent arrows indicate a potential inverted repeat.