The pathway of glucose degradation in some invertebrates

Abstract

1. 1. The pathway of glucose degradation was investigated in molluscs by determining the end products after incubation of the soft tissues with glucose-U-C14. 2. 2. The main product of glucose degradation was found to be succinic acid, with small amounts of lactic acid being formed as well. 3. 3. A mechanism for the formation of succinic acid is proposed on the basis of ancillary information including the relative levels of several enzymes implicated in succinic acid formation. 4. 4. According to the proposed pathway, glucose is degraded to phosphoenolpyruvate (PEP), but most of the PEP is readily carboxylated to oxalacetate by the action of a very active PEP-carboxykinase. Although the molluscs have an active pyruvate kinase, it is quite clear that the rate of carboxylation of PEP is greater than the conversion of PEP to pyruvate. © 1966.