Interaction factors, with cooperative enzymes

The above treatment can be applied to enzymes with 6, 8, or more subunits. In the rate Eq. (13.16), a, b, and c are the factors by which the intrinsic binding constant, XX, has been altered. In the positive cooperativity, these interaction factors have the values less than 1, and in the negative cooperativity they have the values larger than 1. If the interaction factors are equal to one, we have no cooperativity, and expression (13.16) reduces to the Michaelis-Menten equation. The shape of the velocity or the binding curve and the distribution of enzyme species strongly depends on the numerical values of interaction factors (Fig. 5). 

Aloni Y, Delmer D.P., and Benziman M. 1982. Achievement of high rates of in vitro synthesis of 1, 4-beta-D-glucan activation by cooperative interaction of the Acetobacter xylinum enzyme system with GTP, polyethylene glycol, and a protein factor. Proc Natl Acad Sci USA 79(21) 6448-6452. Amikam D. and Benziman M. 1989. Cyclic diguanylic acid and cellulose synthesis in Agrobacterium tumefaciens. J Bacterid 171(12) 6649-6655. 

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