Figure 6.

CINV1 Hydrolyzes Sucrose in Vitro.

(A) Expression and purification of recombinant CINV1. M, protein molecular mass marker; lanes 1 and 2, crude extracts in the absence or presence of isopropylthio-β-galactoside (in a final concentration of 0.5 mM, for 6 h); lane 3, purified recombinant CINV1. The arrow indicates the position of recombinant CINV1.

(B) Invertase activity of purified CINV1 (pH 7.0) under a gradient of sucrose concentrations (25 to 300 mM). The K_m was calculated from data of three independent experiments, and error bars represent se.

(C) Invertase activity of purified CINV1 over a pH range from ∼5.0 to 9.0 at the sucrose concentration of 100 mM. Purified CINV1 showed highest activities in the range from ∼7.0 to 8.0.