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+ | = Parameters for the educatETH <i>E.coli</i> system = | ||
<p> | <p> | ||
- | + | In order to ensure that our simulation results match the biology as close as possible, we tried to find good estimates for the biological system parameters. To this end, we performed an extensive literature review. However, not all parameters were found in the literature, especially those which do not refer to vastly used proteins. Whenever this was the case, logical estimates were provided by our biologists based on empirical values. | |
</p><br> | </p><br> | ||
== Model Parameters == | == Model Parameters == | ||
- | {| class="wikitable" border="1" cellspacing="0" cellpadding="2" style="text-align:left; margin: 1em 1em 1em 0; background: #f9f9f9; border: 1px #aaa solid; border-collapse: collapse;" | + | === General parameters === |
- | ! Parameter | + | {| class="wikitable" width="100%" border="1" cellspacing="0" cellpadding="2" style="text-align:left; margin: 1em 1em 1em 0; background: #f9f9f9; border: 1px #aaa solid; border-collapse: collapse;" |
- | ! Value | + | !width="10%"| Parameter |
- | ! Description | + | !width="10%"| Value |
- | ! Comments | + | !width="20%"| Description |
+ | !width="60%"| Comments | ||
|- | |- | ||
| c<sub>1</sub><sup>max</sup> | | c<sub>1</sub><sup>max</sup> | ||
| 0.01 [mM/h] | | 0.01 [mM/h] | ||
| max. transcription rate of constitutive promoter (per gene) | | max. transcription rate of constitutive promoter (per gene) | ||
- | | promoter no. J23105; | + | | promoter no. J23105; Estimate |
|- | |- | ||
| c<sub>2</sub><sup>max</sup> | | c<sub>2</sub><sup>max</sup> | ||
| 0.01 [mM/h] | | 0.01 [mM/h] | ||
- | | max. transcription rate of | + | | max. transcription rate of LuxR-activated promoter (per gene) |
- | | | + | | Estimate |
|- | |- | ||
| l<sup>hi</sup> | | l<sup>hi</sup> | ||
| 25 | | 25 | ||
| high-copy plasmid number | | high-copy plasmid number | ||
- | | | + | | Estimate |
|- | |- | ||
| l<sup>lo</sup> | | l<sup>lo</sup> | ||
| 5 | | 5 | ||
| low-copy plasmid number | | low-copy plasmid number | ||
- | | | + | | Estimate |
|- | |- | ||
- | | a | + | | a |
- | | | + | | 1% |
- | | basic production | + | | basic production levels |
- | | | + | | Estimate |
|- | |- | ||
- | | | + | |} |
- | | | + | |
- | + | === Degradation constants === | |
- | + | {| class="wikitable" width="100%" border="1" cellspacing="0" cellpadding="2" style="text-align:left; margin: 1em 1em 1em 0; background: #f9f9f9; border: 1px #aaa solid; border-collapse: collapse;" | |
- | + | !width="10%"| Parameter | |
- | + | !width="10%"| Value | |
- | + | !width="20%"| Description | |
- | + | !width="60%"| Comments | |
- | + | ||
- | | | + | |
- | | | + | |
- | | | + | |
- | | | + | |
- | + | ||
|- | |- | ||
- | + | | d<sub>LacI</sub> | |
- | + | | 2.31e-3 [1/s] | |
- | + | | degradation of LacI | |
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | | d<sub> | + | |
- | | 2.31e-3 [ | + | |
- | | degradation of | + | |
| Ref. [10] | | Ref. [10] | ||
|- | |- | ||
- | | d<sub> | + | | d<sub>TetR</sub> |
- | | 1e-5 [ | + | | |
- | | degradation of | + | *1e-5 [1/s] |
- | | Ref. [9] | + | *2.31e-3 [1/s] |
+ | | degradation of TetR | ||
+ | | | ||
+ | *Ref. [9] | ||
+ | *Ref. [10] | ||
|- | |- | ||
- | | d<sub> | + | | d<sub>LuxR</sub> |
- | | 1e-3 - 1e-4 [ | + | | 1e-3 - 1e-4 [1/s] |
- | | degradation of | + | | degradation of LuxR |
| Ref: [6] | | Ref: [6] | ||
|- | |- | ||
- | | d<sub> | + | | d<sub>CI</sub> |
- | | 7e-4 [ | + | | 7e-4 [1/s] |
- | | degradation of | + | | degradation of CI |
| Ref. [7] | | Ref. [7] | ||
|- | |- | ||
- | | d<sub> | + | | d<sub>P22CII</sub> |
+ | | | ||
+ | | degradation of P22CII | ||
| | | | ||
- | |||
|- | |- | ||
| d<sub>YFP</sub> | | d<sub>YFP</sub> | ||
- | | 6.3e-3 [ | + | | 6.3e-3 [1/min] |
| degradation of YFP | | degradation of YFP | ||
| suppl. mat. to Ref. [8] corresponding to a half life of 110min | | suppl. mat. to Ref. [8] corresponding to a half life of 110min | ||
|- | |- | ||
| d<sub>GFP</sub> | | d<sub>GFP</sub> | ||
- | | 6.3e-3 [ | + | | 6.3e-3 [1/min] |
| degradation of GFP | | degradation of GFP | ||
| in analogy to YFP | | in analogy to YFP | ||
|- | |- | ||
| d<sub>RFP</sub> | | d<sub>RFP</sub> | ||
- | | 6.3e-3 [ | + | | 6.3e-3 [1/min] |
| degradation of RFP | | degradation of RFP | ||
| in analogy to YFP | | in analogy to YFP | ||
|- | |- | ||
| d<sub>CFP</sub> | | d<sub>CFP</sub> | ||
- | | 6.3e-3 [ | + | | 6.3e-3 [1/min] |
| degradation of CFP | | degradation of CFP | ||
| in analogy to YFP | | in analogy to YFP | ||
|- | |- | ||
- | | K<sub> | + | |} |
- | | 0.1 - 1 [pM] | + | |
- | | | + | === Dissociation constants === |
- | | Ref. [2] | + | |
+ | {| class="wikitable" width="100%" border="1" cellspacing="0" cellpadding="2" style="text-align:left; margin: 1em 1em 1em 0; background: #f9f9f9; border: 1px #aaa solid; border-collapse: collapse;" | ||
+ | !width="10%"| Parameter | ||
+ | !width="10%"| Value | ||
+ | !width="20%"| Description | ||
+ | !width="60%"| Comments | ||
+ | |- | ||
+ | | K<sub>LacI</sub> | ||
+ | | | ||
+ | * 0.1 - 1 [pM] | ||
+ | * 800 [nM] | ||
+ | | LacI repressor dissociation constant | ||
+ | | | ||
+ | * Ref. [2] | ||
+ | * Ref. [12] | ||
|- | |- | ||
- | | K<sub> | + | | K<sub>IPTG</sub> |
| 1.3 [µM] | | 1.3 [µM] | ||
- | | IPTG- | + | | IPTG-LacI repressor dissociation constant |
| Ref. [2] | | Ref. [2] | ||
|- | |- | ||
- | | K<sub> | + | | K<sub>TetR</sub> |
| 179 [pM] | | 179 [pM] | ||
- | | | + | | TetR repressor dissociation constant |
| Ref. [1] | | Ref. [1] | ||
|- | |- | ||
- | | K<sub> | + | | K<sub>ATC</sub> |
| 893 [pM] | | 893 [pM] | ||
- | | | + | | ATC-TetR repressor dissociation constant |
| Ref. [1] | | Ref. [1] | ||
|- | |- | ||
- | | K<sub> | + | | K<sub>LuxR</sub> |
| 55 - 520 [nM] | | 55 - 520 [nM] | ||
- | | | + | | LuxR activator dissociation constant |
| Ref: [6] | | Ref: [6] | ||
|- | |- | ||
- | | K<sub> | + | | K<sub>AHL</sub> |
| 0.09 - 1 [µM] | | 0.09 - 1 [µM] | ||
- | | AHL- | + | | AHL-LuxR activator dissociation constant |
| Ref: [6] | | Ref: [6] | ||
|- | |- | ||
- | | K<sub> | + | | K<sub>CI</sub> |
| | | | ||
- | * 8 [pM] | + | *8 [pM] |
- | * 50 [nM] | + | *50 [nM] |
- | | | + | | CI repressor dissociation constant |
| | | | ||
- | * Ref. [12] | + | *Ref. [12] |
- | * starting with values of Ref. [6] and using Ref. [3] | + | *starting with values of Ref. [6] and using Ref. [3] |
|- | |- | ||
- | | K<sub> | + | | K<sub>P22CII</sub> |
| 0.577 [µM] | | 0.577 [µM] | ||
- | | | + | | P22CII repressor dissociation constant |
- | | Ref. [11] | + | | Ref. [11] |
|- | |- | ||
- | | n<sub> | + | |} |
- | | 1 | + | |
- | | | + | === Hill cooperativity === |
- | | Ref. [5] | + | {| class="wikitable" width="100%" border="1" cellspacing="0" cellpadding="2" style="text-align:left; margin: 1em 1em 1em 0; background: #f9f9f9; border: 1px #aaa solid; border-collapse: collapse;" |
+ | !width="10%"| Parameter | ||
+ | !width="10%"| Value | ||
+ | !width="20%"| Description | ||
+ | !width="60%"| Comments | ||
+ | |- | ||
+ | | n<sub>LacI</sub> | ||
+ | | | ||
+ | * 1 | ||
+ | * 2 | ||
+ | | LacI repressor Hill cooperativity | ||
+ | | | ||
+ | * Ref. [5] | ||
+ | * Ref. [12] | ||
|- | |- | ||
- | | n<sub> | + | | n<sub>IPTG</sub> |
| 2 | | 2 | ||
- | | IPTG- | + | | IPTG-LacI repressor Hill cooperativity |
| Ref. [5] | | Ref. [5] | ||
|- | |- | ||
- | | n<sub> | + | | n<sub>TetR</sub> |
| 3 | | 3 | ||
- | | | + | | TetR repressor Hill cooperativity |
| Ref. [3] | | Ref. [3] | ||
|- | |- | ||
- | | n<sub> | + | | n<sub>ATC</sub> |
| 2 (1.5-2.5) | | 2 (1.5-2.5) | ||
- | | | + | | ATC-TetR repressor Hill cooperativity |
|Ref. [3] | |Ref. [3] | ||
|- | |- | ||
- | | n<sub> | + | | n<sub>LuxR</sub> |
| 2 | | 2 | ||
- | | | + | | LuxR activator Hill cooperativity |
| Ref: [6] | | Ref: [6] | ||
|- | |- | ||
- | | n<sub> | + | | n<sub>AHL</sub> |
| 1 | | 1 | ||
- | | AHL- | + | | AHL-LuxR activator Hill cooperativity |
| Ref. [3] | | Ref. [3] | ||
|- | |- | ||
- | | n<sub> | + | | n<sub>CI</sub> |
| 2 | | 2 | ||
- | | | + | | CI repressor Hill cooperativity |
| Ref. [12] | | Ref. [12] | ||
|- | |- | ||
- | | n<sub> | + | | n<sub>P22CII</sub> |
| 4 | | 4 | ||
- | | | + | | P22CII repressor Hill cooperativity |
- | | Ref. [11] | + | | Ref. [11] |
|- | |- | ||
|} | |} | ||
+ | |||
+ | <br> | ||
== References == | == References == |
Latest revision as of 14:27, 26 October 2007
Parameters for the educatETH E.coli system
In order to ensure that our simulation results match the biology as close as possible, we tried to find good estimates for the biological system parameters. To this end, we performed an extensive literature review. However, not all parameters were found in the literature, especially those which do not refer to vastly used proteins. Whenever this was the case, logical estimates were provided by our biologists based on empirical values.
Model Parameters
General parameters
Parameter | Value | Description | Comments |
---|---|---|---|
c1max | 0.01 [mM/h] | max. transcription rate of constitutive promoter (per gene) | promoter no. J23105; Estimate |
c2max | 0.01 [mM/h] | max. transcription rate of LuxR-activated promoter (per gene) | Estimate |
lhi | 25 | high-copy plasmid number | Estimate |
llo | 5 | low-copy plasmid number | Estimate |
a | 1% | basic production levels | Estimate |
Degradation constants
Parameter | Value | Description | Comments |
---|---|---|---|
dLacI | 2.31e-3 [1/s] | degradation of LacI | Ref. [10] |
dTetR |
| degradation of TetR |
|
dLuxR | 1e-3 - 1e-4 [1/s] | degradation of LuxR | Ref: [6] |
dCI | 7e-4 [1/s] | degradation of CI | Ref. [7] |
dP22CII | degradation of P22CII | ||
dYFP | 6.3e-3 [1/min] | degradation of YFP | suppl. mat. to Ref. [8] corresponding to a half life of 110min |
dGFP | 6.3e-3 [1/min] | degradation of GFP | in analogy to YFP |
dRFP | 6.3e-3 [1/min] | degradation of RFP | in analogy to YFP |
dCFP | 6.3e-3 [1/min] | degradation of CFP | in analogy to YFP |
Dissociation constants
Parameter | Value | Description | Comments |
---|---|---|---|
KLacI |
| LacI repressor dissociation constant |
|
KIPTG | 1.3 [µM] | IPTG-LacI repressor dissociation constant | Ref. [2] |
KTetR | 179 [pM] | TetR repressor dissociation constant | Ref. [1] |
KATC | 893 [pM] | ATC-TetR repressor dissociation constant | Ref. [1] |
KLuxR | 55 - 520 [nM] | LuxR activator dissociation constant | Ref: [6] |
KAHL | 0.09 - 1 [µM] | AHL-LuxR activator dissociation constant | Ref: [6] |
KCI |
| CI repressor dissociation constant |
|
KP22CII | 0.577 [µM] | P22CII repressor dissociation constant | Ref. [11] |
Hill cooperativity
Parameter | Value | Description | Comments |
---|---|---|---|
nLacI |
| LacI repressor Hill cooperativity |
|
nIPTG | 2 | IPTG-LacI repressor Hill cooperativity | Ref. [5] |
nTetR | 3 | TetR repressor Hill cooperativity | Ref. [3] |
nATC | 2 (1.5-2.5) | ATC-TetR repressor Hill cooperativity | Ref. [3] |
nLuxR | 2 | LuxR activator Hill cooperativity | Ref: [6] |
nAHL | 1 | AHL-LuxR activator Hill cooperativity | Ref. [3] |
nCI | 2 | CI repressor Hill cooperativity | Ref. [12] |
nP22CII | 4 | P22CII repressor Hill cooperativity | Ref. [11] |
References
[http://www.pnas.org/cgi/content/abstract/104/8/2643 [1] Weber W et al.] "A synthetic time-delay circuit in mammalian cells and mice", P Natl Acad Sci USA 104(8):2643-2648, 2007
[http://www.pnas.org/cgi/content/full/100/13/7702?ck=nck [2] Setty Y et al.] "Detailed map of a cis-regulatory input function", P Natl Acad Sci USA 100(13):7702-7707, 2003
[http://ieeexplore.ieee.org/iel5/9711/30654/01416417.pdf [3] Braun D et al.] "Parameter Estimation for Two Synthetic Gene Networks: A Case Study", ICASSP 5:769-772, 2005
[http://www.nature.com/nature/journal/v435/n7038/suppinfo/nature03508.html [4] Fung E et al.] "A synthetic gene--metabolic oscillator", Nature 435:118-122, 2005 (supplementary material)
[http://dx.doi.org/10.1016/j.jbiotec.2005.08.030 [5] Iadevaia S and Mantzais NV] "Genetic network driven control of PHBV copolymer composition", J Biotechnol 122(1):99-121, 2006
[http://dx.doi.org/10.1016/j.biosystems.2005.04.006 [6] Goryachev AB et al.] "Systems analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants", Biosystems 83(2-3):178-187, 2004
[http://www.genetics.org/cgi/content/abstract/149/4/1633 [7] Arkin A et al.] "Stochastic kinetic analysis of developmental pathway bifurcation in phage λ-Infected Escherichia coli cells", Genetics 149: 1633-1648, 1998
[http://download.cell.com/supplementarydata/cell/107/6/739/DC1/index.htm [8] Colman-Lerner A et al.] "Yeast Cbk1 and Mob2 Activate Daughter-Specific Genetic Programs to Induce Asymmetric Cell Fates", Cell 107(6): 739-750, 2001 (supplementary material)
[http://www.nature.com/nature/journal/v405/n6786/abs/405590a0.html [9] Becskei A and Serrano L] "Engineering stability in gene networks by autoregulation", Nature 405: 590-593, 2000
[http://www.biophysj.org/cgi/content/full/89/6/3873?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&searchid=1&FIRSTINDEX=0&volume=89&firstpage=3873&resourcetype=HWCIT [10] Tuttle et al.] "Model-Driven Designs of an Oscillating Gene Network", Biophys J 89(6):3873-3883, 2005
[http://www.pnas.org/cgi/reprint/99/2/679 [11] McMillen LM et al.] "Synchronizing genetic relaxation oscillators by intercell signaling", P Natl Acad Sci USA 99(2):679-684, 2002
[http://www.nature.com/nature/journal/v434/n7037/full/nature03461.html [12] Basu S et al.] "A synthetic multicellular system for programmed pattern formation", Nature 434:1130-1134, 2005