These points are controlled by fast-acting cooperative enzymes that operate in a flip-flop mechanism together with the respective antagonistic enzymes, preventing futile cycles. From an analysis of the oscillatory state, certain control points in the glycolytic chain can be located that coincide with major branching points to other metabolic pathways. However, a quantitative treatment of the overall kinetics is limited by an incomplete knowledge of the enzymes' dynamic and chemical compartmentation as well as some of their control properties. A prominent feature is the high enzyme: substrate ratio, which guarantees fast response times. Functional and regulatory mechanisms of the whole glycolytic reaction pathway. ![]() In addition to the usual Michaelis-Menten saturation kinetics and the various types of inhibition, there is control by positive and negative effectors based on oligomeric structures (fast acting, fine control) as well as regulation by chemical interconversion based on enzyme cascades (slow acting, very effective). A classification of the various types of enzymic control mechanisms operating in the glycolytic pathway is given. Functional properties of the enzymes are reflected in their tertiary and quaternary structures. The same is true for the molarities of catalytic centres in the cytosol, as is noted for yeast. ![]() The catalytic constants of the glycolytic enzymes are remarkably optimized the turnover numbers are within one order of magnitude. Functional and structural properties of individual enzymes. The design of the glycolytic pathway resulting from the continuous refinement of evolution is discussed with regard to three aspects.
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