Glyceraldehyde-3-phosphate dehydrogenase other activities

Aside from PEPCase, a number of other CAM-related genes have been partially characterised (Table 1). These include cDNA clones for pyruvate, orthophosphate dikinase (PPDK), a specific NADP malate dehydrogenase (MDH), glyceraldehyde phosphate dehydrogenase (GaPDH) and NADP-dependent malic enzyme (MOD). Previous studies indicated that the enzymatic activities of these gene products increased upon salt stress in the ice plant (Holtum Winter, 1982). As in the case... 

Other means of control also exist. For instance, phosphoribulose kinase and glyceraldehyde 3-phosphate dehydrogenase also are regulated hy NADPH directly. In the dark, these enzymes associate with a small protein called CP 12 to form a large complex in which the enzymes are inactivated. NADPH generated in the light reactions hinds to this complex, leading to the release of the enzymes. Thus, the activity of these enzymes depends first on reduction by thioredoxin and then on the NADPH-mediated release from CP 12. 

Tables 13-la and 13-lb list only the most important categories of enzyme classes (E.C. s). Some enzymes that are involved in reactions at phosphorus are hidden in other classes. For example glyceraldehyde-3-phosphate dehydrogenase, which catalyses the oxidative phosphorylation of glyceraldehyde-3-phosphate to 1,3-diphospho-glycerate, is classified under E.C. 1.2.1.12 and 1.2.1.13. Neither the name of the enzyme nor its IUB-classification, gives information about the phosphorylating step. Identifying enzymes potentially useful in synthesis that have been ambiguously classified is difficult for those outside of biochemistry because no complete reference is available connecting enzymatic activity with synthetic applicability.

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