Metabolic control analysis - Essay Example

Metabolic control analysis The purpose of metabolic control analysis and how it relates to enzyme kinetics Metabolic control analysis is a model that is used to examine the distribution of fluxes, and other metabolic concentrations in the metabolic pathways among the different enzymes found within the pathway (Heinstra & Geer, 1991). This model presumes that there is a particular measure of flux control distributed within the enzymes. It is useful because it explains how the amount of fluxes and intermediary concentrations depends on some particular network considerations.

The model aids in understanding the control that each enzyme wields on the fluxes and the concentrations (Acerenza & Kacser, 1997). The metabolic control analysis is one way of studying the kinetic behavior of enzymatic systems. Enzyme kinetics is the study of the way enzymes catalyze chemical reactions. Conducting metabolic control analysis helps one understand the effects of properties that particular enzymes posses, and how it affects metabolic fluxes and concentrations. By use of this model, it is possible to tell how changes in enzymatic concentration affect the sensitivity of metabolic variables such as fluxes and metabolic concentrations.

Therefore, the metabolic control analysis helps in the calculation of these sensitivities, otherwise known as flux control coefficients of enzymes from their elasticities, or kinetic properties. The procedures used in the calculations are modified to suit the most complex pathway designs. Hence, mathematical procedures have been derived to enable calculation of the effects of the flux control coefficients according to their intensity. All this information is necessary in the understanding of how the enzyme networks functions.

It, therefore, becomes possible to predict their reaction to any disturbance out of the norm, such as environmental disruptions (Heinstra & Geer, 1991).Various ways by which one can estimate flux control coefficients Control coefficients determine the relative change in fluxes and concentrations, which occurs as a response to environmental and genetic changes upon the enzymes. There are various ways in which these coefficients are estimated. One way is the single modulation, which is a simple method, used in cases where only one enzyme is disrupted.

Another method is the double modulation. In this method, two steps are employed in the study of a pathway and without knowing the kinetic properties in advance, and then kinetic properties are known after the analysis is conducted. This method is advantageous because the values of the changes do not have to be known in advance. According to the analysis of Acerenza and Cornish-Bowden (1990), this characteristic makes the method flexible so that it can be used upon different structures of different sizes.

References Acerenza, L. & Cornish-Bowden, A. (1997). Generalization of the double-modulation method for in situ determination of elasticities. Biochem, Journal, 327, 217-223. Acerenza, L. & Kacser, H. (1990). Enzyme kinetics and metabolic control. A method to test and quantify the effect of enzymic properties on metabolic variables. Biochemical Journal, 269 (3), 697-707.Heinstra, P. H. & Geer, B. W. (1991). Metabolic Control Analysis and Enzyme Variation: Nutritional Manipulation of the Flux from Ethanol to Lipids in Drosophila. Mol. Biol. Evol., 8(5), 703-708.