The gap1 Operon of the Cyanobacterium Synechococcus PCC 7942 Carries a Gene Encoding Glycogen Phosphorylase and Is Induced under Anaerobic Conditions

The cloning and sequencing of the gap1 operon, which encodes the glycolytic NAD-specific glyceraldehyde-3-phosphate dehydrogenase in the cyanobacterium Synechococcus PCC 7942, showed that the gap1 gene is closely linked to the glgP gene encoding glycogen phosphorylase (an enzyme that catalyzes the first step of glycogen degradation). Northern blotting experiments showed that the gap1 and glgP genes are coexpressed and organized in a bicistronic operon, whose expression is enhanced under anaerobic conditions. The nucleotide sequence of the operon has been submitted to GenBank under accession number AF428099.