Fig 2.

Stimulatory effect of deproteinized cell extracts on SR. Deproteinized extracts from HEK 293 (293 extr.) and primary astrocyte (Ast. extr.) cultured cells elicit an increase in D-serine synthesis (A) and pyruvate production (B) by recombinant SR. Reaction media contained 20 mM Tris⋅HCl (pH 7.4), 15 μM PLP, and 10 mM L-serine and 0.15 mg/ml of recombinant SR-GST. The reaction was stopped after 1 h at 37°C, and the samples were assayed for D-serine and pyruvate. The results represent the average ± SEM of three to five experiments carried out with different protein preparations.