Glycolysis in yeast

Some of the main types of cellular regulation associated with rhythmic behavior are listed in Table III. Regulation of ion channels gives rise to the periodic variation of the membrane potential in nerve and cardiac cells [27, 28 for a recent review of neural rhythms see, for example, Ref. 29]. Regulation of enzyme activity is associated with metabolic oscillations, such as those that occur in glycolysis in yeast and muscle cells. Calcium oscillations originate... 

Glycolysis in yeast has been intensively studied especially under anaerobic conditions. Here, one of these previous kinetic studies is augmented by the core reactions of the xenobiotic ketone. The used model of glycolysis was devised by Hynne et al. and contains 22 variables for concentrations of involved metabolites and 24 reactions [53]. This model quantitatively accounts for most known details of enzyme regulation in order to precisely describe the supercritical onset of oscillations as observed experimentally [49, 82]. The following extensions have been introduced to the literature model (Fig. 3.4) ... 

Balanced Truncation in Action Reduction of a Silicon Cell Model of Glycolysis in Yeast... 

Here a model of glycolysis in yeast [26] is reduced using the model reduction method outlined above. Glycolysis is the well known process that uses glucose to produce Gibbs energy-rich compounds such as pyruvate, and is depicted in Fig. 15.1. 

J. A. Den Hollander, K. Ugurbil, T. R. Brown and R. G. Shulman (1981). Phosphorus-31 nuclear magnetic resonance studies on the effect of oxygen upon glycolysis in yeast. Biochemistry, 20, 5871-5880. 

Winfree, A.T. 1972b. Oscillatory glycolysis in yeast The pattern of phase resetting by oxygen. Arch. Biochem. Biophys. 149 388-401. 

Figure 5.8. Block diagram of glycolysis in yeast metabolism including stoichiometric (---- ) and informative (-->) interactions. (From Hess and Boiteux, 1973.)...

It is a matter of common observation that most metabolic sequences operate most of the time at considerably less than maximal rate. This generalization is especially evident in higher animals—the respiratory rate of muscle at rest, for example, is a small fraction of the rate of working muscle—but it is valid for other types of organisms as well. The observation that glycolysis in yeast proceeds at less than the maximal rate in the presence of air (the Pasteur effect) attracted much interest for years. 

The detailed investigations on the mechanism of glycolysis in yeast and muscle stimulated similar studies on those nonpbotoiynthetic plant tissues which were capable of elaborating alcohol. These studies uncovered metabolic intermediates identical with those found in yeast and muscle. Tank6 (344) found that upon incubation peas accumulated fructose-6-phosphate and fructose-l,6-diphosphate. When Hanes (143) observed the dissimilation of starch by pea seed... 

Although Harden and Young had observed in 1904 that a heat-stable factor, cozymase, was essential for glycolysis in their yeast preparations,... 

This is similar to the situation when, if all the glycolytic enzymes, plus activators and co-factors are placed together, in a flask or tube, glucose will be converted to lactic acid or ethanol, i.e. a mixture of enzymes plus co-factors can carry out a process that occurs in a living cell (e.g. muscle or yeast). Such experiments on the enzymes of glycolysis, in a flask, were hrst performed by Th. Buchner over 100 years ago. 

Other forms of vanadium have been implicated in the stimulation of the plasma membrane vanadate-dependent NAD(P)H oxidation reaction. Decavanadate has been shown to be a more potent stimulator of the vanadate-dependent NADH oxidation activity than added orthovanadate [30,31], Interestingly, decavanadate reductase activity has been found to be an alternative activity of an NADP-specific isocitrate dehydrogenase [32], Diperoxovanadium derivatives have also been shown to be involved in this type of reaction [33,34], Decavanadate may play a role in the biological role of vanadium, as it is found in yeast cells growing in the presence of orthovanadate [8] and is a potent inhibitor of phosphofructokinase-1, the control step of glycolysis, and other metabolic reactions [35],... 

Conversion to ethanol. In yeast and some other microorganisms under anaerobic conditions, the NAD+ required for the continuation of glycolysis is regenerated by a process called alcoholic fermentation. The pyruvate is converted to acetaldehyde (by pyruvate decarboxylase) and then to ethanol (by alcohol dehydrogenase), the latter reaction reoxidizing the NADH to NAD+ ... 

The production of ethanol uses the glycolysis pathway, a common biochemical pathway that is present in animals as well as in yeast and bacteria. In this pathway glucose is commonly converted to pyruvate when oxygen is present (aerobiosis), but if oxygen is lacking (anaerobiosis), ethanol is produced. 

Hynne, F., Dano, S., Sorensen, P. G., A full-scale model for yeast glycolysis in Sac-charomyces cerevisiae, Biophys. Chem. 2001, 94 121-163. 

In the early days of enzyme study attention was focused mainly on glycolysis in muscle, fermentation in yeast and oxidative phosphorylation, all of which provided the basis for vast and rapid development of biochemistry. Dixon and Webb estimated the number of enzymes to be about 650 in their book, Enzyme, in 1957. The number has grown to about 3000 at the present time and continues to increase (Fig. I. 1). 

Davies, S.E. and Brindle, K.M. (1992) Effects of overexpression of phosphofructokinase on glycolysis in the yeast Saccharomyces cerevisiae. Biochemistry 31,4729 735. 

Sutton DD, Arnow PM, Lampen JO. Effect of high concentrations of nystatin upon glycolysis and cellular permeability in yeast. 

Much has been published on the controversial subject of the control of glycolysis. The following brief summary of some of the controls responsible for the Pasteur effect in yeasts is based mainly on a review by Sols and coworkers144 (see also, Fig. 7). (i) Isocitrate dehydrogenase (NAD ) (EC 1.1.1.41), one of the controlling enzymes of the tricarboxylic acid cycle (see Fig. 5), catalyzes the reaction... 

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