InterPro: IPR009164 Fructose-1,6-bisphosphatase, Bacillus type

Fructose 1,6-bisphosphatase catalyses the hydrolysis of fructose 1,6-bisphosphate to fructose 6-phosphate [1]. This is an essential reaction in the process of gluconeogenesis, the process by which non-carbohydrate precursors are converted to glucose, and hence this enzyme is found almost universally. Enzyme activity can be regulated by a number of different mechanisms including AMP inhibition, cylic AMP-dependent phosphorylation and light-dependent-activation.

This entry represents a group of fructose 1,6-bisphosphatases found within the Firmicutes (low GC Gram-positive bacteria) which do not show any significant sequence similarity to the enzymes from other organisms. The Bacillus subtilis enzyme is inhibited by AMP, though this can be overcome by phosphoenolpyruvate, and is dependent on Mn(2+) [2, 3]. Mutants lacking this enzyme are apparently still able to grow on gluconeogenic growth substrates such as malate and glycerol.