Levels of transcription of genes involved in NADPH biosynthesis in C. glutamicum ΔAPER::gapC, ΔAPRE::rocG, and ΔAPE::rocG-R::gapC compared with those in the parental strain, C. glutamicum ΔAPER. ΔAPER::gapC (white bars), ΔAPRE::rocG (black bars), and ΔAPE::rocG-R::gapC (hatched bars)