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Result: 1 - 4 of 4 rows are displayed

Enzyme List for pathway Ras (Pathway Number 76) in Accession Synaptic_Network (Accession Number 16)

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 GEF-Gprot-bg /
GEF-bg_act-ras
Ras

Pathway No. 76
0.5050510.024explicit E-S complexSubstrate: 
GDP-Ras
Product : 
GTP-Ras
  Kinetics based on the activation of Gq by the receptor complex in the Gq model (in turn based on the Mahama and Linderman model) k1 = 2e-5, k2 = 1e-10, k3 = 10 (I do not know why they even bother with k2). Lets put k1 at 2e-6 to get a reasonable equilibrium More specific values from, eg.g: Orita et al JBC 268(34) 25542-25546 from rasGRF and smgGDS: k1=3.3e-7; k2 = 0.08, k3 = 0.02
2 GEF* /
GEF*-act-ras
Ras

Pathway No. 76
0.5050510.024explicit E-S complexSubstrate: 
GDP-Ras
Product : 
GTP-Ras
  Kinetics from Orita et al JBC 268(34):25542-25546. Note that the Vmax is slow, but it does match the slow GTP hydrolysis rates.
3 GAP /
GAP-inact-ras
Ras

Pathway No. 76
1.010410100explicit E-S complexSubstrate: 
GTP-Ras
Product : 
GDP-Ras
  From Eccleston et al JBC 268(36)pp27012-19 get Kd < 2uM, kcat - 10/sec From Martin et al Cell 63 843-849 1990 get Kd ~ 250 nM, kcat = 20/min I will go with the Eccleston figures as there are good error bars (10%). The two sets of values are reasonably close. k1 = 1.666e-3/sec, k2 = 1000/sec, k3 = 10/sec (note k3 is rate-limiting) This is one of the rare cases where we have direct info on the k3 being rate-limiting. Hence the ratio I use for the k2:k3 rates is 100 rather than the usual 4.
4 CaM-GEF /
CaM-GEF-act-ras
Ras

Pathway No. 76
0.5050510.024explicit E-S complexSubstrate: 
GDP-Ras
Product : 
GTP-Ras
  Kinetics same as GEF-bg_act-ras

 
Result: 1 - 4 of 4 rows are displayed



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