EC Number   |
Substrates |
Organism |
Products |
Reversibility |
|---|
   2.7.12.2 | more |
development of a continuous spectrophotometric assay for mitogen-activated protein kinase kinases. The assay relies on the measurement of phosphoprotein product generated in the first step of the MAPK kinase reaction. Dephosphorylation of the phosphoprotein is coupled to a MAPK phosphatase, MKP3, to generate phosphate, which is then used as the substrate of purine nucleoside phosphorylase to catalyze the N-glycosidic cleavage of 2-amino 6-mercapto 7-methyl purine ribonucleoside. Of the reaction products ribose 1-phosphate and 2-amino 6-mercapto 7-methylpurine, the latter has a high absorbance at 360 nm relative to the nucleoside and, hence, provides a spectrophotometric signal that can be continuously followed. In the presence of excess phosphatase, the phosphorylated protein substrate molecules undergo dephosphorylation almost immediately after their formation. The steady-state use of the resultant inorganic phosphate is a reflection of the constant initial velocity of the exchange reaction. Method development and evaluation, overview |
Homo sapiens |
? |
- |
? |
| 2.7.12.2 | more |
development of a continuous spectrophotometric assay for mitogen-activated protein kinase kinases. The assay relies on the measurement of phosphoprotein product generated in the first step of the MAPK kinase reaction. Dephosphorylation of the phosphoprotein is coupled to a MAPK phosphatase, MKP5, to generate phosphate, which is then used as the substrate of purine nucleoside phosphorylase to catalyze the N-glycosidic cleavage of 2-amino 6-mercapto 7-methyl purine ribonucleoside. Of the reaction products ribose 1-phosphate and 2-amino 6-mercapto 7-methylpurine, the latter has a high absorbance at 360 nm relative to the nucleoside and, hence, provides a spectrophotometric signal that can be continuously followed. In the presence of excess phosphatase, the phosphorylated protein substrate molecules undergo dephosphorylation almost immediately after their formation. The steady-state use of the resultant inorganic phosphate is a reflection of the constant initial velocity of the exchange reaction. Method development and evaluation, overview |
Homo sapiens |
? |
- |
? |
| 2.7.12.2 | more |
interaction of ZmMKK1 and ZmMEKK1, a MAP kinase kinase kinase, in vitro |
Zea mays |
? |
- |
? |
| 2.7.12.2 | more |
the enzyme displays both serine/threonine and tyrosine kinase activities in autophosphorylation reactions as well as in phosphorylation of the exogenous myelin basic protein substrate. Ability of Pfnek3 to autophosphorylate on both the serine/threonine and the tyrosine residues. The dual-specificity activity of the kinase is distinctly influenced by the type of divalent cation present |
Plasmodium falciparum |
? |
- |
? |
| 2.7.12.2 | more |
MKK3 positively regulates PR gene expression and plays a role in defense against Pst DC3000. MKK3 is an upstream activator of the group C MAPKs MPK1, MPK2, MPK7, and MPK14, overview |
Arabidopsis thaliana Col-0 |
? |
- |
? |
