Metabolic control principles

Intensified metabolic control, especially in case of diabetes, demands minimal-invasive or non-invasive methods of analytical measurement. For this goal, a method has been developed to measure the blood glucose content in vivo, in direct contact with the skin, by means of diffuse reflection near infrared (NIR) spectroscopy on the basis of multivariate calibration and neural networks (Muller et al. [1997] Fischbacher et al. [1997] Danzer et al. [1998]). Because no patients with any standard blood glucose value are available in principle, a method of indirect calibration has... 

Principles of metabolic control enzymes, substrates, inhibitors and genes... 

CH 3 PRINCIPLES OF METABOLIC CONTROL ENZYMES, SUBSTRATES, INHIBITORS AND GENES... 

The overall flux of a pathway can be controlled by regulation of just one or two key reactions. As you study metabolic control, look out for the following principles ... 

Clear statement of the principles of metabolic control analysis. 

Herman, R. H., R. M. Cohn, and P. D. McNamara, Principles of Metabolic Control in Mammalian Systems. New York and London Plenum Press, 1980. Discusses various as-... 

The conversion of cholesterol into bile acids represents the most obvious example of the high capacity of the liver to convert lipid-soluble material into excretable water-soluble products. In principle, the reactions in the formation of bUe acids are very similar to those generally involved in the metabolism and detoxication of various lipids and drugs hydroxylations, oxidations, and conjugations. In contrast to detoxication reactions, however, some of the reactions are highly specific and at least one of the hydroxylations is subject to metabolic control. In view of the importance of the rate of elimination of cholesterol in diseases such as atherosclero-... 

The object of metabolic control theory is to provide a sound mathematical foundation for the quantitative estimation of the role played by individual enzymes on the control of flux through a metabolic pathway and also the control exerted by individual enzymes on the concentration of intermediate metabolites in the pathway. The general principles of metabolic control theory and biochemical systems theory can be visualized by considering the simple metabolic pathway in Fig. 6. The numbers above the arrows... 

MetaboUc flux analysis has not yet been applied to this system. It has been suggested that an extension of the principles of metabolic control theory would make it possible to identify rational optimal strategies for improvement of ergot alkaloid formation [4]. 

All major network sciences seem to concur on the view that real networks are not random but are based on robust and strong organizational principles. As explained above, major metabohc network analysis techniques could be strongly influenced by the network reductionist approach, where the behavior of the network could be potentially predicted by its elementary constituents and their interactions alone. Therefore, the hierarchical and scale-free property of gene networks can effectively complement techniques like metabolic control analysis and become a vital tool in future gene network analysis (Almaas and Barabasi, 2006). 

Theoretical biology attempts to construct basic principles of biology and, by derivation therefrom, to describe the behavior of biological systems. As such, the principles of metabolic control form a subset of the basic principles of theoretical biology. 

While it is beyond the scope of this chapter to enter into the details concerning the physical and chemical principles involved or to consider all of the biochemical reactions which occur according to such principles, the reader may wish to consult some standard references to enhance his appreciation of this theorem (e.g., Metzler, 1977 Florkin and Stotz, 1962-1977 Mahler and Cordes, 1971). Our focus in this chapter will be to explore what constitutes a principle of intracellular metabolic control and to enumerate the various principles so far as we perceive them. 

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