Pyruvate from Entner-Doudoroff pathway

Fig. 1. Pathways of glucose metabolism in eubacteria and eukaryotes. The three major catabolic pathways are the Embden-Meyerhof glycolytic sequence (solid lines), the Entner-Doudoroff pathway (heavy solid lines) and the pentose phosphate pathway (dashed lines). The sequence from glyceraldehyde 3-phosphate to pyruvate is common to all three pathways.

In Tp. acidophilum we have also found the production of pyruvate and glyceraldehyde via a non-phosphorylated Entner-Doudoroff pathway [2,14]. Furthermore, we have demonstrated that the glyceraldehyde is oxidised to glycerate, which is then converted to 2-phosphoglycerate by glycerate kinase. Enolase and pyruvate kinase complete the production of a second molecule of pyruvate (Fig. 3). Again, we have characterised the pathway enzymically and by the identification of intermediates [14], and evidence for its in vivo operation has been gained from radiorespirometric studies [2]. 

The enzymes placed in class IV are from bacteria mainly utilizing the Entner—Doudoroff pathway, and the ADP-Glc PPases are distinctively activated by Fru 6-P and pyruvate, with ADP, AMP, and P behaving as inhibitors. " Included in this group are Agrobacterium tumefaciens and Arthrobacter viscosus. Photosynthetic... 

There are ADP-Glc PPases from organisms capable of having the Embden-Meyerhofif and Entner-Doudoroff pathways as well as anaerobic photosynthetic reductive carboxylic acid pathway. These ADP-Glc PPases are activated by three effectors Fru 1,6-bisP, Fru 6-P, and pyruvate. These three activators place them in class V (Table... 

Fig, 21,3 Entner-Doudoroff pathway in Zymomonas, (It is of biochemical interest that in this pathway the carboxyl oups of the pyruvate arise from the carbon atoms 1 and 4 of the ucose. In the glycolytic pathway, the pyruvate comes from atoms 3 and 4.)... 

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