I've tried many times, but unsuccessfully. I performed homogenisation in 50mM Tris buffer pH 7,6, which contained 1mM EDTA, 1mM MgCl2, 10mM β-merkaptoetanol, 1mM DTT, 0,5% PVP. Also, I used PMSF instead of DTT.

For the reaction I used 50mM Tris buffer, pH 8 or 7.5 (I tested both cases), 5mM MgCl2, 1mM NADH, 5mM OAA.