Glycolysis reactions

All of the glycolysis reactions ranging from phosphoenolpyruvate to fructose 1,6-bisphosphate are reversible, and the phosphoenolpyruvate molecules formed are consumed for producing fructose 1,6-bisphosphate by making use of the same glycolysis enzymes. 

The transesterification and glycolysis reactions proceed via the Aac2 mechanism described above in Section 2.1. The reactions are acid catalyzed as demonstrated by Chegolya el al. [27], who added TPA to the polycondensation of PET and observed a significant increase of the apparent reaction rate. The industrial polycondensation process is accelerated by the use of metal catalysts, with these being mainly antimony compounds. 

Table 2.5 Kinetic data obtained for transesterification/glycolysis reactions... 

Summary of anaerobic glycolysis. Reactions involving the production or consumption of ATP or NADH are indicated. The irreversible reactions of glycolysis are shown with thick arrows. DHAP = dihydroxyacetone phosphate. 

It is difficult to suppress the reverse (glycolysis) reaction that occurs during the preparation of polyesters, though Griehl and Schnock [63] virtually eliminated it. Their results and later data of Challa [69], who took the reverse reaction into account, agree quite well. Griehl and Schnock proposed first-order kinetics however, if account is taken of the gradual increase in over-all rate coefficient, their data fit second-order kinetics better [69]. 

The second-order rate coefficients k and k for the polycondensation and glycolysis reaction of PET, showed roughly the same dependence on... 

Fructose-1,6-diphosphate aldolase of rabbit muscle has been studied very extensively-and it is now commercially available. That of spinach leaves, obviously very accessible, was recently examined (Valentin and Bolte 1993). In the fundamental reaction of glycolysis (reaction 6.8), the donor is dihydroxyacetone phosphate. It can scarcely be varied, but there is more flexibility with the acceptor (David et al. 1991 Bednarski et al. 1989), and sometimes we can wander considerably from the subject of sugar chemistry. In any case, the vicinaZ-diol created at positions 3 and 4 (uloses numbering) has the D-threo configuration. Hence the condensation of the keto aldehyde 6.28 gives ketose 6.29 which, after isolation, is dephosphorylated enzymically in the presence of acid phosphatase. 

An analysis of the influence of enzyme cooperativity in the mathematical model of product activated oscillatory glycolysis reaction was made by Goldbetter and Venieratos (1980). They established the relationship between the instabilities and the value of the Hill coefficient in the allosteric model for phosphofructokinase. 

Aminolysis of rigid PU foam wastes takes place at higher reaction rates than the glycolysis reaction and at lower temperatures (160-170 °C instead of 190-210 °C) [31-33]. 

The glycolysis reaction consists of the stepwise addition of finely ground rigid PU foam wastes, to DEG with a continuous screw feeder, in the presence of a catalyst (NaOH,... 

The names of the enzymes involved in the ten successive glycolysis reaction steps, as per Figure 3.1, are (1) hexokinase, (2) hexose phosphateisomerase, (3) phosphofructokinase, (4) aldolase, (5) triosphosphate isomerase, (6) glyceraldehyde-... 

See also Glycolysis Reaction Summaries, Molecular Intermediates, Glycolysis/Gluconeogenesis Regulation, Gluconeogenesis, Aerobic vs Anaerobic Glycolysis, Pyruvate... 

The acyl-phosphate group at position 1 is much more energy rich than the phosphate anhydride of ATP, so 1,3BPG has the energy to drive synthesis of ATP from ADP + Pi, which it does in the glycolysis reaction catalyzed by the enzyme phosphoglycerate kinase. 

See also Reactions/Energies of Glycolysis, Reaction Picture... 

See also Glycolysis, Gluconeogenesis, The C4 Cycle (from Chapter 17), Glycolysis Reaction Summaries, PEPCK, Enolase, Pyruvate Kinase... 

In animal cells and lactic acid bacteria, pyruvate is converted to lactate. In this case, NADH adds electrons to pyruvate, forming NAD+ and lactate. The NAD+ can then catalyze reaction 6 of further glycolysis reactions. Lactate appears to be produced under aerobic cellular conditions as well, however, so the role of lactate formation is not completely clear. 

Reaction pathway. A listing of sequential chemical species in a reaction mechanism is called a reaction pathway for example, the sequence glucose 6-phosphate, fructose 6-phosphate, fructose 1,6-bisphophate (see fig. 1.2) is a reaction pathway in the glycolysis reaction mechanism. 

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