Figure 8
Model of IpsA function. In Corynebacteria and Mycobacteria, myo-inositol (mIno) is an important building block for cell wall components and mycothiol. mIno can be taken up from the culture medium or synthesized from glucose-6-phosphate (G6P) via 1D-myo-inositol-3-phosphate (I3P). When mIno concentration is low, IpsA activates ino1, encoding myo-inositol phosphate synthase, which catalyzes the formation of I3P from G6P. Besides ino1, IpsA activates or represses several other targets of unknown function.