Miriam van Santen writes:
>I'm working on a computer simulation model of the TCA cycle. I'm trying
>to find out if there is anything known about the flux distribution from
>isocitrate to either succinate and glyoxylate or a-ketoglutarate. The
>concentration of malate, succinate and p-enol-pyruvate have a negative
>feedback on the conversion of isocitrate into succinate and glyoxylate.
>Is there a mathematical description for these inhibitions known?
Apart from the simulations and data that Pedro Mendes has referred you to,
kinetics of the allosteric inhibition of isocitrate lyase are referred to in
Ashworth & Kornberg, Biochim. Biophys. acta, 73, 519-522, 1963. The
isocitrate dehydrogenase in E. coli is subject to inactivation by protein
phosphorylation; see Walsh & Koshland, J. Biol. Chem. 260, 8430-8437 (1985)
for details. Walsh & Koshland varied the split between TCA cycle and
glyoxalate cycle by varying the expression of citrate synthase in E. coli,
PNAS 82, 3577, (1985).
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