Metabolism of carbohydrate derivatives by Pseudomonas acidovorans

Wild-type Pseudomonas acidovorans strain A1 was unable to grow on glycerol or glucose as sole source of carbon and energy although it grew well on gluconate. Spontaneous glycerol-positive mutants, which apparently had become permeable to glycerol, were readily isolated, but glucose-positive mutants did not occur. P. acidovorans lacked glucose dehydrogenase and glucokinase, which were sufficient to account for its inability to grow on glucose. Gluconate was degraded exclusively via a noncoordinately induced Entner-Doudoroff pathway. Phosphogluconate dehydrogenase was undetectable. In contrast to P. aeruginosa, P. acidovorans possessed a single glyceraldehyde-phosphate dehydrogenase activity, which was NAD+ specific and constitutive, and an inducible pyruvate kinase. Moreover, growth of glycerol-positive strain K2 on glycerol did not induce any of the enzymes related to metabolism of hexosephosphate derivatives as occurs in fluorescent pseudomonads.