Figure 8.

DJ-1 does not deglycate BSA. A, 1.5 ml of 100 μm BSA was incubated with 100 mm DJ-1 in PBS for 2 h at 37 °C. BSA was purified by two rounds of size exclusion on PD-10 columns and placed into a protein concentrator. At the indicated time points, ∼20 μl of flow-through solution was used to measure MGO concentration by DNPH. B, the same sample of glycated and purified BSA as in A was incubated with 30 μm DJ-1 or 10 μm Glx3. Aliquots were taken at 30 and 90 min to measure l-lactate using a lactate peroxidase assay. The experiment was repeated three times; representative data are shown. In all cases, the amount of l-lactate produced by DJ-1 or Glx3 did not significantly exceed the amount of free MGO right after purification of glycated BSA.