Gamma-glutamyl phosphate reductase signature

γ-glutamyl phosphate reductase (EC 1.2.1.41) (GPR) is the enzyme that catalyzes the second step in the biosynthesis of proline from glutamate, the NADP-dependent reduction of L-glutamate 5-phosphate into L-glutamate 5-semialdehyde and phosphate.

In eubacteria (gene proA) and yeast [1] (gene PRO2), GPR is a monofunctional protein, while in plants and mammals, it is a bifunctional enzyme (P5CS) [2] that consists of two domains: a N-terminal glutamate 5-kinase domain (EC 2.7.2.11) (see <PDOC00701>) and a C-terminal GPR domain.

As a signature pattern, we selected a conserved region that contains two histidine residues. This region is located in the last third of GPR.