[View Larger Version of this Image]

Figure S4. Comparison of NADH/NADPH ratios in parental HL-60 and Raji cells and respiration-deficient cell clones. Cell extracts (550 µl; equivalent to 5.5 x 10⁶ cells) from the parental cells (HL-60 and Raji) and eight ρ^- clones were prepared and subjected to HPLC analysis, as described in Materials and methods. (A) Representative HPLC chromatograms of NADH and NADPH standards (top), perchloric acid extracts of parental HL-60 cells (middle), and HL60-C6F ρ^- cells (bottom). AU, absorbance unit at 340 nm. (B) Quantitative comparison of the NADH/NADPH ratios in parental HL-60 and Raji cells and their respiratory-deficient ρ^- clones. The ratio for each cell line was calculated by dividing the peak area of NADH by that of NADPH in the same chromatogram.