FIG. 1.

RH regulatory activity in the hyp deletion strains. R. eutropha strains harboring the plasmid-based Φ(hoxK′-lacZ) fusion were grown in FGN medium in the absence (black bars) or in the presence (white bars) of hydrogen. Cells were harvested at an optical density at 436 nm (OD₄₃₆) of 8.0 ± 0.3, and the β-galactosidase activity was determined according to the protocol of Miller (28). Lane 1, HF470; lane 2, HF510; lane 3, HF503; lane 4, HF504; lane 5, HF505; lane 6, HF506; lane 7, HF507; lane 8, HF508; lane 9, HF509.