Subsystem: Glycolysis and Gluconeogenesis
This subsystem's description is:
This Subsystem has been constructed by Ross Overbeek and is currently maintained by Sveta Gerdes. This SS describes mostly eubacteria, archaeal EMP with its unique enzymes and fascinating variations is encoded in SS “Glycolysis and Gluconeogenesis, including Archaeal enzymes”.
Glycolysis (Embden-Meyerhof-Parnas pathway, EMP) is the most common sequence of reactions for the conversion of glucose-6-P into pyruvate in all domains of life. It generates ATP, reduced equivalents, and precursor metabolites for a multitude of essential cellular processes. During growth on substrates other then sugars, essential glycolytic intermediates are synthesized via glyconeogenesis, reversion of EMP. While Glycolysis and glyconeogenesis (as well as other central metabolic routes) are well-conserved in bacteria and eukaryotes, Archaea have developed unique variants of EMP, presented in separate subsystem: “Glycolysis and Gluconeogenesis, including Archaeal enzymes”. A diagram of this pathway is posted on FIG Forum at: http://brucella.uchicago.edu/SubsystemForum/showthread.php?p=350#post350
Out of 10 enzymatic steps, which constitute classical EMP, 7 are reversible and work in glyconeogenesis as well. However, glycolytic reactions catalyzed by the following enzymes are not reversible:
(i) 6-phosphofructokinase (EC 2.7.1.11),
(ii) Pyruvate kinase (EC 2.7.1.40),
(iii) some forms of glyceraldehyde 3-phosphate dehydrogenase (see below)
They are bypassed during glyconeogenesis via:
(i) Fructose-1,6-bisphosphatase (EC 3.1.3.11),
(ii) PEP synthase (EC 2.7.9.2) or/and Pyruvate,phosphate dikinase (EC 2.7.9.1),
(iii) NAD(P)-dependent glyceraldehyde 3-phosphate dehydrogenase
respectively or by utilizing other central metabolic pathways.
For more information, please check out the description and the additional notes tabs, below
Diagram | Functional Roles | Subsystem Spreadsheet | Description | Additional Notes | Scenarios | |||||||||
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