Fig. 1.
Diagram of plasmids - 1SP_PE, 1S1C_Tφ, 1S1W+_Tφ, and 1S1W-_Tφ - constructed with one or more of the following transcription elements: a synthetic T7 promoter, SP; a consensus T7 promoter, CP; a T7 class II promoter, WP; and a terminator (Tφ). The arrows show the direction of transcription. The short, vertical bars represent BamH I cleavage sites. The scale bar (bottom) is in kb.