|PROSITE documentation PDOC00421|
Phosphoenolpyruvate carboxykinase (GTP) (EC 126.96.36.199) (PEPCK)  catalyzes the formation of phosphoenolpyruvate by decarboxylation of oxaloacetate while hydrolyzing GTP, a rate limiting step in gluconeogenesis (the biosynthesis of glucose). In vertebrates there are two isozymes: a cytosolic form whose activity is affected by hormones regulating this metabolic process (such as glucagon, or insulin) and a mitochondrial form.
An essential cysteine residue has been proposed  to be implicated in the catalytic mechanism; this residue is located in the central part of PEPCK and is in the center of a perfectly conserved region that we use as a signature pattern.Note:
April 2006 / Pattern revised.
PROSITE method (with tools and information) covered by this documentation:
|1||Authors||Weldon S.L., Rando A., Matathias A.S., Hod Y., Kalonick P.A., Savon S., Cook J.S., Hanson R.W.|
|Title||Mitochondrial phosphoenolpyruvate carboxykinase from the chicken. Comparison of the cDNA and protein sequences with the cytosolic isozyme.|
|Source||J. Biol. Chem. 265:7308-7317(1990).|
|2||Authors||Lewis C.T., Seyer J.M., Carlson G.M.|
|Title||Cysteine 288: an essential hyperreactive thiol of cytosolic phosphoenolpyruvate carboxykinase (GTP).|
|Source||J. Biol. Chem. 264:27-33(1989).|