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Result: 1 - 6 of 6 rows are displayed

Enzyme List for pathway MAPK (Pathway Number 182) in Accession MAPK-bistability-fig1c (Accession Number 35)

Entries are grouped according to Pathway Number and they are alternately color coded using  and   color.
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  Enzyme Molecule /

 Enzyme Activity
Pathway Name / 
Pathway No.
Km
(uM)
kcat
(s^-1)
Ratio
(k2/k3)
Enzyme TypeReagents
1 MAPKK* /
MAPKKtyr
MAPK

Pathway No. 182
0.04629630.154explicit E-S complexSubstrate: 
MAPK
Product : 
MAPK-tyr
  The actual MAPKK is 2 forms from Seger et al JBC 267:20 14373(1992) Vmax = 150nmol/min/mg From Haystead et al FEBS 306(1):17-22 we get Km=46.6nM for at least one of the phosphs. Putting these together: k3=0.15/sec, ratio of 4 to get k2=0.6. k1=0.75/46.6nM=2.7e-5 In terms of Michaelis-Menten rates, Km = 0.046, Vmax = 0.15, ratio = 4.
2 MAPKK* /
MAPKKthr
MAPK

Pathway No. 182
0.04629630.154explicit E-S complexSubstrate: 
MAPK-tyr
Product : 
MAPK*
  Rate consts same as for MAPKKtyr.
3 RGR /
RGR.1
MAPK

Pathway No. 182
0.1590910.1054explicit E-S complexSubstrate: 
MAPKK
Product : 
MAPKK-ser
  Kinetics are the same as for the craf-1* activity, ie., k1=5.5e-6, k2=.42, k3 =0.105 These are based on Force et al PNAS USA 91 1270-1274 1994.
4 RGR /
RGR.2
MAPK

Pathway No. 182
0.1590910.1054explicit E-S complexSubstrate: 
MAPKK-ser
Product : 
MAPKK*
  Same kinetics as other c-raf activated forms. See Force et al PNAS 91 1270-1274 1994. k1 = 5.5e-6, k2 = .42, k3 = 0.105
5 Raf*-GTP-Ras /
Raf*-GTP-Ras.1
MAPK

Pathway No. 182
0.1590910.1054explicit E-S complexSubstrate: 
MAPKK
Product : 
MAPKK-ser
  Kinetics are the same as for the craf-1* activity, ie., k1=1.1e-6, k2=.42, k3 =0.105 These are based on Force et al PNAS USA 91 1270-1274 1994. They report Km for MAPKK of 0.8 uM. and a Vmax of ~500 fm/min/ug. These parms cannot reach the observed 4X stimulation of MAPK. So we increase the affinity, ie, raise k1 5x to 5.5e-6 which is equivalent to 5-fold reduction in Km to about 0.16. This is, of course, dependent on the amount of MAPKK present.
6 Raf*-GTP-Ras /
Raf*-GTP-Ras.2
MAPK

Pathway No. 182
0.1590910.1054explicit E-S complexSubstrate: 
MAPKK-ser
Product : 
MAPKK*
  Same kinetics as other c-raf activated forms. See Force et al PNAS 91 1270-1274 1994.

 
Result: 1 - 6 of 6 rows are displayed



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