Utilization of fructose and glutamate by Rhodospirillum rubrum

Fructose served as sole carbon source for the growth of Rhodospirillum rubrum anaerobically under light or aerobically in the dark while glucose did not. Glucose was not utilized by the organism at all. Radiorespirometric studies, using 14C specifically labelled fructose as substrate, revealed that fructose is catabolized exclusively via the Embden–Meyerhof–Parnas (EMP) glycolytic pathway. Both L-glutamic and D-glutamic acids can be utilized by this organism, via the tricarboxylic acid cycle (TCA) pathway, under either aerobic-dark or anaerobic-light conditions.