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Result: 1 - 7 of 7 rows are displayed

Reaction List for pathway AC (Pathway Number 85) in Accession Synaptic_Network (Accession Number 16)

Entries are grouped according to Pathway Number and they are alternately color coded using  and  color.
Further ordering can be done to the table header.  indicates that ordering is done according to ascending or descending order.
Keq is calculated only for first order reactions.
Kd is calculated only for second order reactions. [nA+nB <->nC or nA<->nC+nD, where n is number and A,B,C,D are molecules]
  Reaction
Name
Pathway Name / 
Pathway No.
KfKbKdtauReagents
1 CaM-bind-AC1AC

Pathway No. 85
49.9998
(uM^-1 s^-1)
1
(s^-1)
Kd(bf) = 0.02(uM)-  Substrate:
 CaM-Ca4
 AC1

 Products:
 AC1-CaM
  Half-max at 20 nM CaM (Tang et al JBC 266:13 8595-8603 1991 Assume a rapid CaM binding of 1/sec.
2 dephosph-AC2AC

Pathway No. 85
0.1
(s^-1)
0
(s^-1)
--  Substrate:
 AC2*

 Products:
 AC2
  Rate constrained by balancing levels of phosphorylated form, especially given resting PKC levels.
3 Gs-bind-AC2AC

Pathway No. 85
499.998
(uM^-1 s^-1)
1
(s^-1)
Kd(bf) = 0.002(uM)-  Substrate:
 AC2
 Gs-alpha

 Products:
 AC2-Gs
  Half-max at around 3nM = kb/kf from fig 5 in Feinstein et al PNAS USA 88 10173-10177 1991 kf = kb/1800 = 5.56e-4 kb Ofer Jacobowitz's thesis data indicates it is more like 2 nM. Jacobowitz, PhD Thesis, Mount Sinai School of Medicine.
4 Gs-bind-AC1AC

Pathway No. 85
126
(uM^-1 s^-1)
1
(s^-1)
Kd(bf) = 0.0079(uM)-  Substrate:
 Gs-alpha
 AC1

 Products:
 AC1-Gs
  Half-max 8nM from Tang et al JBC266:13 8595-8603 kb/kf = 8 nM = 4800#/cell Also assume rapid binding of 1/sec.
5 Gs-bind-AC2*AC

Pathway No. 85
833.28
(uM^-1 s^-1)
1
(s^-1)
Kd(bf) = 0.0012(uM)-  Substrate:
 Gs-alpha
 AC2*

 Products:
 AC2*-Gs
  Various references: Jacobowitz et al JBC 268(6):3829-3892 show that AC2 has a 2x rise in basal activation on phosphorylation, and a 2x rise in forskolin stimulated activation. Yoshimura and Cooper JBC 1993 268(7):4604-4607 say that type II is stimulated 9x over basal. Lustig et al 1993 JBC 268(19):13900-13905 syow a 2x activation by PDBu, and the Gs stimulated response is increased 2x-4x by PDBu. To match all these results with the binding of the unphosphorylated form we use a Kd of 1.2 nM here as compared with the Kd of 2 nM for the unphosphorylated reaction.
6 dephosph-PDEAC

Pathway No. 85
0.1
(s^-1)
0
(s^-1)
--  Substrate:
 cAMP-PDE*

 Products:
 cAMP-PDE
  The rates for this are poorly constrained. In adipocytes (probably a different PDE) the dephosphorylation is complete within 15 min, but there are no intermediate time points so it could be much faster. Identity of phosphatase is still unknown.
7 CaM_bind_PDE1AC

Pathway No. 85
720
(uM^-1 s^-1)
5
(s^-1)
Kd(bf) = 0.0069(uM)-  Substrate:
 PDE1
 CaM-Ca4

 Products:
 CaM.PDE1
  Borisy et al J Neurosci 12(3):915-923 For olf epithelium PDE1, affinity is 7 nM CaM and about 2 uM Ca which is consistent with it binding Ca4.CaM at 7 nM. Assume same for brain. Reaction should be pretty fast. Assume kb = 5/sec.

 
Result: 1 - 7 of 7 rows are displayed



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