|PROSITE documentation PDOC00701 [for PROSITE entry PS00902]|
Glutamate 5-kinase (EC 18.104.22.168) (γ-glutamyl kinase) (GK) is the enzyme that catalyzes the first step in the biosynthesis of proline from glutamate, the ATP-dependent phosphorylation of L-glutamate into L-glutamate 5-phosphate.
In eubacteria (gene proB) and yeast  (gene PRO1), GK is a monofunctional protein, while in plants and mammals, it is a bifunctional enzyme (P5CS)  that consists of two domains: a N-terminal GK domain and a C-terminal γ-glutamyl phosphate reductase domain (EC 22.214.171.124) (see <PDOC00940>).
As a signature pattern, we selected a highly conserved glycine-and alanine-rich region located in the central section of these enzymes.
Yeast hypothetical protein YHR033w is highly similar to GK.Last update:
December 2004 / Pattern and text revised.
PROSITE method (with tools and information) covered by this documentation:
|1||Authors||Li W., Brandriss M.C.|
|Title||Proline biosynthesis in Saccharomyces cerevisiae: molecular analysis of the PRO1 gene, which encodes gamma-glutamyl kinase.|
|Source||J. Bacteriol. 174:4148-4156(1992).|
|2||Authors||Hu C.-A.A., Delauney A.J., Verma D.P.S.|
|Title||A bifunctional enzyme (delta 1-pyrroline-5-carboxylate synthetase) catalyzes the first two steps in proline biosynthesis in plants.|
|Source||Proc. Natl. Acad. Sci. U.S.A. 89:9354-9358(1992).|