Figure 4.

Mycobacterium tuberculosis H-NS binds to the Holliday junction with high affinity. Reaction mixtures contained 5 nM of ³²P-labeled HJ (A), ³²P-labeled DNA replication fork (B) or ³²P-labeled Y-shaped junction (C) in the absence (lane1) or presence of 10, 25, 50,100, 150, 200, 250, 300 or 500 nM H-NS (lanes 2–10), respectively. The open triangle on the top of the gel denotes increasing concentrations of H-NS. Reaction products were separated as described under ‘Experimental Procedures’ section. The positions of free DNA and protein–DNA complexes are shown in the left-hand side of each panel. (D) Graphical representation of the extent of binding of H-NS to different DNA substrates in (A–C) is plotted versus varying concentrations of H-NS.