Analysis of transcriptional coupling of C10 protease genes and inhibitor genes in B. thetaiotaomicron VPI-5482. The left-hand side of the diagram shows the organization of the protease loci according to the colour scheme in Figure 1. The small black horizontal arrows represent the location of the PCR primer sites in the sequence, and the number between pairs of inverted arrows is the expected amplicon size in bp. The right-hand side of the diagram shows an agarose gel of the observed amplicons with the following lane assignments: Lane 1: btpA; Lane 2: btpA-btiA; Lane 3: btpB-btpC; Lane 4: btpB; Lane 5: btpB-btiB; Lane 6: btpC; Lane 7: btiZ and Lane 8: btpZ-btiZ. The top of the gel in on the right, with small white inverted triangles indicate the positions of the size markers in kb.