Functionality of RNase P proteins (rnpA genes) from A. ehrlichii, H. halophila, M. infernorum, T. indicus, and T. nitratireducens in the RNase P protein complementation test strain B. subtilis d7, including B. subtilis (Bsu) rnpA as positive control. The homologous/heterologous rnpA genes were expressed in B. subtilis d7 from vector pDG148(S/X) under control of the spac promoter. Single colonies of B. subtilis d7 transformed with different rnpA expression plasmids were spotted onto LB agar plates supplemented with xylose (Xyl, permissive conditions) or glucose (Glu, nonpermissive conditions). Complementation efficiency was documented after 19, 24, and 45 h (shown here) of incubation at 37°C. The figure shows one representative experiment out of three independent ones. For further details, see Materials and Methods.
