3 Adenosine Diphosphoryl Glucose Pyrophosphorylase

Abstract

This chapter discusses adenosine diphosphoryl glucose pyrophosphorylase. A consistent pattern is usually observed among the source (plant or microorganism) of the adenosine diphosphate (ADP) glucose pyrophosphorylase, the metabolites that are most effective as activators of the enzyme, and the type of carbon utilization pathway occurring in that tissue or organism. The Enterobacteria accumulating glycogen contain an ADPglucose pyrophosphorylase activated by fructose-dip, triphosphopyridine nucleotide (TPNH), and pyridoxal-5'-P and inhibited by 5'-adenylate. These organisms are known to use glycolysis as their main route for glucose catabolism. Another class of ADPglucose pyrophosphorylase is found in Aeromonas formicans that is activated by either fructose 6-P or fructose 1,6-diP. In contrast, Serratia marcescens, an enteric, has an ADPglucose pyrophosphorylase not activated by any metabolite tested. A group of organisms that catabolize glucose via the Entner-Doudoroff pathway contains an ADPglucose pyrophosphorylase activated both by fructose 6-P and pyruvate. The ADPglucose pyrophosphorylase found in leaves of plants and in green algae is activated by 3-phosphoglycerate. The activators for the various groups of ADPglucose pyrophosphorylase are significant metabolites in the metabolic pathways utilized by the plant tissues or microorganisms.