Accéder au contenu
MilliporeSigma

Glycerol kinase, the pacemaker for the dissimilation of glycerol in Escherichia coli.

Journal of bacteriology (1970-06-01)
N Zwaig, W S Kistler, E C Lin
RÉSUMÉ

The activity of glycerol kinase is rate-limiting in the metabolism of glycerol by cells of Escherichia coli. A mutant strain producing a glycerol kinase resistant to inhibition by fructose-1,6-diphosphate grows faster than its wild-type parent on glycerol as the sole source of carbon and energy. The amount of intracellular fructose-1,6-diphosphate was determined for wild-type cells growing exponentially on glycerol. The water content of such cells was also determined, allowing calculation of the intracellular concentration of fructose-1,6-diphosphate. This value, 1.7 mm, is adequate to exert substantial inhibition on the wild-type glycerol kinase. The desensitization of glycerol kinase to feedback inhibition also enhances the power of glycerol to exert catabolite repression, both on the enzymes of the glycerol system itself and on those of the lactose system. However, desensitization of glycerol kinase alone does not eliminate the phenomenon of diauxic growth in a glucose-glycerol medium. Biphasic growth in such a medium is abolished if the altered enzyme is produced constitutively. The constitutive production of the mutant kinase at high levels, however, renders the cells vulnerable to glycerol. Thus, when the cells have been grown on a carbon source with a low power for catabolite repression, e.g., succinate, sudden exposure to glycerol leads to overconsumption of the nutrient and cell death.

MATÉRIAUX
Référence du produit
Marque
Description du produit

Sigma-Aldrich
Glycerokinase from Cellulomonas sp., lyophilized powder, 25-75 units/mg protein
Sigma-Aldrich
Glycerokinase from Escherichia coli, 300-600 units/mL, ammonium sulfate suspension
Sigma-Aldrich
Glycerokinase from Escherichia coli, lyophilized powder, 40-100 units/mg protein
Sigma-Aldrich
Glycerokinase from Bacillus stearothermophilus, buffered aqueous solution, ≥75 units/mg protein (biuret)