Feedback Regulation of Arginine Biosynthesis in Blue-Green Algae and Photosynthetic Bacteria

Abstract

A number of blue-green algae and photosynthetic bacteria synthesize arginine from glutamate via acetylated intermediates. Cell-free extracts of these photosynthetic microorganisms contain an N-acetyl glutamate phosphokinase, which is specifically inhibited by arginine. They also contain a transacetylase which forms ornithine from aN-acetyl ornithine and glutamate. The transacetylase appears to be specific for L-glutamate. Arginine synthesis and its regulation by feedback inhibition in photosynthetic microorganisms differ from that in Escherichia coli and other Enterobacteriaceae.