Fig 4.

(A) G6PDH activities separated on native gels following in vitro incubation with increasing concentration of NADPH and NADP⁺. The extracts (about 10 μg), prepared from MW179-1D and CBS2359 cultures grown on YPD, were incubated overnight on ice with the cofactors, fractioned on polyacrylamide gels, and stained for G6PDH. (B, left panel) Absorbance spectra from MW179-1D extract following the addition of 0.3 mM NADP⁺. (Right panel) Effect of concentration of NADP⁺ on the initial velocity of NADPH reduction. The solid line is the best fit, according to the Michaelis-Menten equation. (C) Absorbance spectra from CBS2359 extract following the addition of 0.3 mM NADP⁺. (D) An experiment as described for panel A but with extracts from an S. cerevisiae culture grown on YPD and human rabdomiosarcoma cell lines. The values in boxes beneath the gels indicate the percentage of each G6PDH band in each lane, as for Fig. 2.