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Result: 1 - 12 of 12 rows are displayed

Reaction List for pathway CaRegulation (Pathway Number 110) in Accession NonOsc_Ca_IP3metabolism (Accession Number 23)

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 Ca5-bind-CalCaRegulation

Pathway No. 110
0.0005
(uM^-5 s^-1)
1
(s^-1)
--  Substrate:
 Calseq
 Ca-sequester
 Ca-sequester
 Ca-sequester
 Ca-sequester
 Ca-sequester

 Products:
 Ca5-Cal
 There are actually 5 Ca-sequester substrates for this reaction, along with one Calseq. Due to system limitations only four are entered.
2 CaTraspATPaseCaRegulation

Pathway No. 110
25
(s^-1)
0
(#^-2 s^-1)
Not applicable**-  Substrate:
 CaTransp-2Ca

 Products:
 CaTransp
 Ca-sequester
 Ca-sequester
  kCa3 = 2 * Ca transporter rate since each step has 2 Ca++. = 0.5 uM/sec from Lauffenburger and Linderman 1993 Receptors pg200 The amount of the activated transporter is about 0.01 uM = 6e3#. from runs. So 0.01uM * kf * 2 = 0.5 uM/sec (no back reaction) so kf = 25, kb = 0 Alternatively, 6e3 * kf = 0.25 * 6e5, giving the same kf
3 
  • Ca-bind-to-Trans
    p
  • CaRegulation

    Pathway No. 110
    3600
    (uM^-2 s^-1)
    144
    (s^-1)
    Kd(af) = 0.2(uM)-  Substrate:
     Ca
     Ca
     CaTransp

     Products:
     CaTransp-2Ca
      Rates from Lauffenburger abd Linderman 1993 Receptors pg 200. Kd = KCa2 = 0.2 uM
    4 IP3RbindCaRegulation

    Pathway No. 110
    0.05
    (uM^-3 s^-1)
    1
    (s^-1)
    Kd(af) = 2.7144(uM)-  Substrate:
     IP3R
     IP3
     IP3
     IP3

     Products:
     IP3R*
      Based on Lauffenburger and Linderman 1993 Receptors pg 200. The binding of IP3 on this reaction had a Hill coeff of 3. The eqns of Mahama and Linderman (cited in the book as 1993 a) are equivalent to the binding all occurring in a single step, so that is how I do it in this version. Their Ki1 is 0.07 uM. Lots of other data sources: Ramos-Franco et al, Biophys J 75, 1998: 834-39 have Ca sensitivity curves. At 250 nM free Ca, the EC50 for type1 is 58 nM and type 2 is 194 nM. Type 3 would be about 2 uM according to Newton et al, JBC 268(46), 1994: 28613-19. For the purposes of this model we use a Kd of 2.7 uM which is high but maybe OK at low calcium. The details of Ca interaction with the IP3R are not included in this model.
    5 
  • inactivate_cap_
    Ca
  • CaRegulation

    Pathway No. 110
    0
    (#^-2 s^-1)
    1
    (s^-1)
    Not applicable**-  Substrate:
     Ca-sequester
     Ca-sequester
  •  capacitive_Ca_
    entry*


     Products:
     inact_cap_entry
  •   The Kd is set at about 3 uM so that at resting Ca the capacitative Ca entry is almost blocked. A 2nd order response makes the response steep.
    6 Ca10-bind-CalCaRegulation

    Pathway No. 110
    0.0005
    (uM^-5 s^-1)
    1
    (s^-1)
    --  Substrate:
     Ca5-Cal
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester

     Products:
     Ca10-Cal
     There are actually 5 Ca-sequester substrates for this reaction, along with Ca5-Cal. Due to system limitations only four are entered.
    7 Ca15-bind-CalCaRegulation

    Pathway No. 110
    0.0005
    (uM^-5 s^-1)
    1
    (s^-1)
    --  Substrate:
     Ca10-Cal
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester

     Products:
     Ca15-Cal
     There are actually 5 Ca-sequester substrates for this reaction, along with Ca10-Cal. Due to system limitations only four are entered.
    8 Ca20-bind-CalCaRegulation

    Pathway No. 110
    0.0005
    (uM^-5 s^-1)
    1
    (s^-1)
    --  Substrate:
     Ca15-Cal
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester

     Products:
     Ca20-Cal
     There are actually 5 Ca-sequester substrates for this reaction, along with Ca15-Cal. Due to system limitations only four are entered.
    9 Ca25-bind-CalCaRegulation

    Pathway No. 110
    0.0005
    (uM^-5 s^-1)
    1
    (s^-1)
    --  Substrate:
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca20-Cal

     Products:
     Ca25-Cal
     There are actually 5 Ca-sequester substrates for this reaction, along with Ca20-Cal. Due to system limitations only four are entered.
    10 Ca30-bind-CalCaRegulation

    Pathway No. 110
    0.0005
    (uM^-5 s^-1)
    1
    (s^-1)
    --  Substrate:
     Ca25-Cal
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester

     Products:
     Ca30-Cal
     There are actually 5 Ca-sequester substrates for this reaction, along with Ca25-Cal. Due to system limitations only four are entered.
    11 Ca35-bind-CalCaRegulation

    Pathway No. 110
    0.0005
    (uM^-5 s^-1)
    1
    (s^-1)
    --  Substrate:
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca30-Cal

     Products:
     Ca35-Cal
     There are actually 5 Ca-sequester substrates for this reaction, along with Ca30-Cal. Due to system limitations only four are entered.
    12 Ca40-bind-CalCaRegulation

    Pathway No. 110
    0.0005
    (uM^-5 s^-1)
    1
    (s^-1)
    --  Substrate:
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca-sequester
     Ca35-Cal

     Products:
     Ca40-Cal
     There are actually 5 Ca-sequester substrates for this reaction, along with Ca35-Cal. Due to system limitations only four are entered.

     
    Result: 1 - 12 of 12 rows are displayed



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