Figure 1.

Biochemical Analysis of Recombinant AAE3 Protein.

(A) SDS-PAGE gel of nickel affinity–purified His-AAE3 protein stained with Coomassie blue. Right lane, His-AAE3; left lane, molecular weight markers.

(B) Optimum pH for AAE3 was determined using 300 μM oxalate as substrate and two buffer systems: sodium phosphate for pH 5.0 to 8.0 and Tris-HCl for pH 7.5 to 10.0. Data are the mean ± se of two replicates.

(C) Kinetic analysis of AAE3 was performed using oxalate concentrations from 50 to 1200 μM oxalate. K_m and V_max were determined from nonlinear regression to the Michaelis-Menten equation for concentrations of oxalate up to 500 μM from five replicate experiments.