Fig. 1

TthHB27I digestion patterns comparison in the presence of DMSO and cofactor SAM or its analogues. 0.5 μg of 1789 bp PCR DNA substrate (see Additional file 1) was incubated with 2 U of TthHB27I for 1 h at 65 °C in REase buffer with increasing amount of DMSO. Reaction mixtures were precipitated and electrophoresed in 1.3% agarose/TBE gels. The pictures on the right side of the figure show the theoretical arrangement of the DNA bands in an agarose gel after digesting the substrate DNA with TthHB27I under standard conditions. a Digestions performed only with the addition of DMSO, without any cofactor. Lane M1, GeneRuler 1 kb DNA Ladder; lane M2, 100 bp Plus DNA Ladder; lane K, undigested PCR fragment; lane 1, 0% (v/v) DMSO present in the reaction mixture; lane 2, with 5% (v/v) DMSO; lane 3, with 10% (v/v) DMSO; lane 4, with 15% (v/v) DMSO; lane 5, with 20% (v/v) DMSO; lane 6, with 25% (v/v) DMSO; lane 7, with 30% (v/v) DMSO. As in (a), but in the presence of 100 μM SAM (b); 100 μM SIN (c); 100 μM SAC (d); 100 μM SAH (e); 100 μM ATP (f)