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Fig. 3 | BMC Biology

Fig. 3

From: Using mathematical models to understand metabolism, genes, and disease

Fig. 3

Effect of short-term variation in amino acid input on metabolite levels and reaction velocities in the folate and methionine cycles. Three pulses of amino acids are shown by gray bars below the figures, corresponding to three meals over a 24-hour period. Variation in response is shown as percentage deviation from the mean. a Two metabolites (SAM and 5mTHF) and reaction velocities [cystathionine β-synthase (CBS) and MTHFR] that show complementary responses. b Reaction velocities of mitochondrial and cytosolic serinehydroxymethyltransferase (SHMT; values below −100 % are reversals of direction of the reaction). c Dynamic variation of fluxes throughout the pathway stabilize the velocities of DNMT, TS, and AICART and the concentration of glutathione. d Eliminating product inhibition by S-adenosylhomocysteine (SAH) increases the sensitivity of the DNMT reaction to variation in input is indicated by the greater amplitude of the response. After [28, 35]

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