Fluctuating enzyme

Blumenfeld L A, Burbajev D S and Davydov R M 1986 Processes of conformational relaxation in enzyme catalysis The Fluctuating Enzyme ed E R Welch (New York Wiley) pp 369-402... 

Welch, G.R. (Ed.) (1985) The Fluctuating Enzyme, John Wiley and Sons, New York. 

Lumry, R. and Gregory, R.B. (1986) Free energy management in protein reactions concepts, complications, and compensation, in Welch, G. R. (eds.) The fluctuating enzymes. Wiley, New York, pp 3-185. 

One example where product inhibition obviously plays a role in living cells is ergoline alkaloid formation in Claviceps (D 21.2). In mycelial mats of Claviceps developing in stationary batch cultures the intracellular concentration of ergoline alkaloids and the activity of dimethylallyl-pyrophosphate L-tryptophan dimethylallyltransferase (DMAT synthase) measurable in homogenates undergo fluctuations Enzyme activity tends to decrease when the intracellular alkaloid concentration is at a maximum. This oscillation may be explained by... 

Gavish, B (1986). Molecular dynamics and the transient strain model of enzyme catalysis. In The Fluctuating Enzyme, ed G. R. Welch. New York John Wiley Sons Inc. 

Analysis of the scheme in Fig. 6.61 demonstrates that the fluctuating enzyme with only two conformational channels can display complex kinetic behavior including substrate inhibition (Fig. 6.62A), sigmoidal kinetics (Fig. 6.62B), convex biphasic (Fig. 6.63A and B), and concave biphasic behavior (Fig. 6.63C). The first three phases exhibit positive cooperativity, whereas the last one shows negative cooperativity, observed experimentally. 

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