Escher map of core pathways in iIsor850. An Escher map consists of metabolites (circles) connected via reactions (lines) which indicate directionality of allowable fluxes (arrows). The core components of iIsor850 were drawn and placed according to relevant classifications. For clarity, not all reactions for the metabolites are shown, and some metabolites occur more than once (i.e., cofactors). Amino acid biosynthesis is indicated in blue, nucleotide biosynthesis is brown, lipid biosynthesis is purple, cell wall biosynthesis is green, fatty acid biosynthesis and elongation is yellow, cofactors and prosthetic groups biosynthesis is red. Central metabolism is uncolored in the middle-top of the figure. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)