FIG. 5.

In vitro interaction between HupUV and various forms of the HupT protein. Conditions of incubation are the same as in Fig. 2. All samples contained 40 pmol of HupUV, and the additions were as follows. Lanes: 1, no further addition; 2, 60 pmol of wild-type HupT; 3, 180 pmol of wild-type HupT; 4, 80 pmol of PAS domain; 5, 160 pmol of PAS domain; 6, 60 pmol of H217N HupT; 7, 180 pmol of H217N HupT; and 8, 100 pmol of PAS-deleted HupT. After migration onto a 7.5% native acrylamide gel, the hydrogenase activity of HupUV was detected in the presence of H₂ and 2 mM BV.