FIG. 3.

Purification and characterization of bacterially expressed Tol1. (A) Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of Tol1. Lane 1, crude extract from E. coli transformed with the Tol1 expression plasmid; lane 2, the purified Tol1 protein. The numbers on the left indicate the molecular masses of the markers in kilodaltons. (B) Inhibition of the 3′(2′),5′-bisphosphate nucleotidase activity of Tol1 by LiCl (●) and NaCl (○). Assays were performed under standard conditions as described in Materials and Methods, and cations were added to the mixture as indicated. The data represent an average of three independent experiments, each sample done in duplicate. The bars indicate standard errors of the mean.