Figure 5.

pH dramatically affects sPPase activity. Recombinant p26.1a and p26.1b sPPase samples were assayed in 50 mm propionic acid (pH 5–7.5) in the presence of 2 mm Na₄P₂O₇ as a substrate, and the amount of inorganic phosphorous (Pi) released was measured (n = 4).