MONTE-CARLO SPREADSHEET MODELING OF STABLE-ISOTOPE BIOSYNTHESIS

Metabolic physiologists often introduce stable isotopes, atoms contain ing additional neutrons, into molecules during biosynthesis. This tags the newly synthesized material by altering its mass. Monte Carte anal ysis is implemented on a popular spreadsheet to analyze this process. An example is provided where acetoacetate is synthesized by condensati on of two acetate moieties. The precursor acetate is present as a mixt ure of natural, and C-13 enriched, acetate. Monte Carlo spreadsheet mo deling captures the complexity of the multi-species isotope biosynthes is by repetitively performing multiple simultaneous Boolean calculatio ns. The effects of increasing the number of molecules synthesized on t he goodness of fit of between model and an exact analytical solution i s illustrated.