activities: Activity computation
In SimEvolEnzCons: Simulation of Evolution of Enzyme Under Constraints

Description Usage Arguments Details Value References Examples

Computes the enzyme pseudo-activities

1	activities(kin_fun,Keq_fun)

`kin_fun`	Numeric vector of kinetic parameters (catalytic constant kcat divided by Michaelis constant Km)
`Keq_fun`	Numeric vector of equilibrium constants

Computes the pseudo-activities of enzymes, i.e. for each enzyme, the product of its kcat/Km (kinetic parameters) by the product of the upstream reactions equilibrium constants.

In other functions, pseudo-activity is also named activity.

kin_fun and Keq_fun need to have the same length.

Numeric vector of activities of each enzyme, of same length as kin_fun and Keq_fun.

Lion, S., F. Gabriel, B. Bost, J. Fiévet, C. Dillmann, and D. De Vienne, 2004. An extension to the metabolic control theory taking into account correlations between enzyme concentrations. European Journal of Biochemistry 271:4375–4391.

#Values from CoA metabolism
kin <- c(53/0.29,50/0.78,29,6.22) #kinetic parameters kcat/Km
Keq <- c(1.1e+8,4.9e+3,1.1e+3,0.228) #equilibrium constants
A <- activities(kin,Keq) #activities

# results : A = c(1.827586e+02, 7.051282e+09, 1.563100e+13, 3.687838e+15)