a) Gene alignment of repC and and its mutant derivative pDOP-TtMC from position 658 to 822, indicating nucleotide changes introduced into pDOP- TtMC (red letters) to increase the C+G content of this region. Note that the included mutations did not change the RepC protein sequence. b) DNA duplex stability expressed as ΔG along repC gene (red line) and its mutant derivative TtMC (blue line). c) Graphic showing A+T content along repC gene and its mutant derivative TtMC. A+T average in both genes is the same: 0.475. The A+T rich region of repC is boxed. Note that the equivalent region in TtMC, also boxed, the A+T content is above the average.