FIG. 6.

Direct measurement of ctaC mRNA. A culture of wild-type strain RB1 was grown in Schaeffer’s medium with or without glucose, and total cellular RNA was isolated at T_−0.5, T₀, T₁, T₂, T₃, and T₄. The reverse-transcribed first-strand cDNA from primer ctaCB1 was amplified by PCR with primer pair ctaCB1-ctaCF1. The location of the primers is shown in Fig. 4. The 338-bp amplified ctaC fragments were separated by electrophoresis on a 1% agarose gel containing 0.5 μg of ethidium bromide per ml. As controls, plasmid pAI536 and H₂O were treated as total cellular RNA was. The growth conditions and timing are indicated.