Team:BCCS-Bristol/Modeling-Parameters

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Modelling Parameters

Bacteria

Attribute	Value	Strain	Justification	Reference
Length	2μm	MG1655	Values come from the University of Alberta’s datasheet on MG1655, produced to aid modelling. There is variability in size between strains - for instance, AW405 length varies between 1.5±0.2μm. But University of Alberta datasheet is specifically for MG1655.	[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
Diameter	0.8μm	MG1655		[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
Shape	Circle r =0.714μm	MG1655	Actually rod-like. A circle with r= 0.714μm will have equivalent surface area to rod-like.	[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
Mass	1.02x10^-13g	MG1655	Given 1x10^-12g for cell wet weight. Dividing this by gravity (=9.81) gives mass.	[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
Swimming Speed	50μms^-1	MG1655	University Alberta's datasheet gives 50μms^-1. However, Swimming speed is affected by: Viscosity (as viscosity increases the speed increases to some maximum, then decreases as the viscosity increases further. E.coli (strain:KL227 of length: 1.0μm and diameter: 0.5μm) maximum speed occurs at viscosity 8cp. Temperature Culture medium Vary strain to strain. Experimental methods Various papers give different speeds for E. coli (most papers provide information on AW405 with a speed of ~20μms^-1). The speed itself is nearly uniform during the run. The wet lab may need to measure this experimentally as we are unaware of the conditions that the speed for MG1655 was obtained. Alberta's value is higher than other values, but this probably because MG1655 is a motile strain.	[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta] [http://www3.interscience.wiley.com/cgi-bin/fulltext/71003069/PDFSTART A Method for Measuring Bacterial Chemotaxis Parameters in a Microcapillary]

Run Tumble Motion

Attribute	Value	Strain	Justification	Reference
Aspartate concentration detected by E. coli	Over ~5 orders of magnitude, 10nM up to 10mM. Can detect changes of as little as ~0.1%	N/A	E. coli detect small changes in concentration of 0.1% via temporal comparisons (4s) over a large range ( 10^-8 to 10^-3 ). Most computer simulations of chemotaxis are based on experimentally determined rates and concentrations. As a result they predict that the minimum detectable concentration of Aspartate is at ~200 nM. Experiments performed by Segall et al. in 1986, exposed tethered E. coli cells to iontophoretically delivered quantities of chemoattractant. These experiments indicated that a change in receptor occupancy of as little as 1/600 could produce an detectable change in swimming behaviour. With a K_d of 1 µM, this corresponds to a minimum detectable concentration of about 2 nM Aspartate. Wild type E. coli cells can detect <10nM of Asp and respond to Asp concentrations of upto 1mM,(responding to over ~5 orders of magnitude). M)	[http://www.jbc.org/cgi/reprint/281/41/30512 Competitive and Cooperative Interactions in Receptor Signalling Complexes]
Temporal comparison of chemotactic gradient	4 seconds	N/A	The past second has positive weighting, the previous 3 seconds have negative weighting. E coli compares past and present concentrations by comparing the average occupancy of the receptors over the 4s. Models reflecting this system have been developed by Segall et al and Schnitzer, cells compare their average receptor occupancy between 4 and 1 s ago c_1-4 to the average receptor occupancy during the last second c_0-1 . Hence b= c_0-1 - c_1-4 . If b>0, the cell reduces the tumbling rate to T_tumbling from the ambient value T₀ , 1s^-1 e.g. b>0 don't tumble. b< 0, tumble at a rate of 1s^-1	[http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=387059&blobtype=pdf Temporal comparisons in bacterial chemotaxis] [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TBN-4CVRC68-2&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=470c7fd73fb9ebf4ca43342f365e221f#sec5.1 Quantitative analysis of signalling networks] [http://web.mit.edu/biophysics/papers/PNAS2003b.pdf Motility of Escherichia coli cells in clusters formed by chemotactic aggregation]
Tumbling angle	Shape parameter 4 Scale parameter 18.32 Location parameter -4.6	AW405	The tumble angle appears not to be dependant on the concentration gradient of chemoattractants/repellents. Nor is there correlation between the length of the run and the change in direction. The program uses a gamma distribution that fits the data collected by Berg and Brown. Several groups though, have observed that the tumble angle is not noramlly distributed but suggest that non-normality was only due to the experimental methods used e.g. in the capillary tube. Tumbling can cause a change in direction when as few as one flagella moves out of the bundle.	[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. coli anaylsed by three-dimensions] [http://bioinformatics.oxfordjournals.org/cgi/reprint/21/11/2714 AgentCell: a digital single-cell assay for bacterial chemotaxis] [http://jb.asm.org/cgi/reprint/189/5/1756 On Torque and tumbling in swimming Escherichia coli]
Tumble angle direction	Bidirectional	AW405	Personal communication with Howard Berg. 'The direction is random, more or less, but there is a slight forward bias. It varies from tumble to tumble. The turn-angle distribution peaks at 68° rather than 90°. Tumbles turn out to be more complex than believed in 1972. Motors switch independently, and a tumble can occur if one or just a few motors change their directions of rotation. Tumbles are short, as judged by the tracking microscope, because they involve filament physics rather than motor physics: a transformation in polymorphic form, following motor reversal, from normal to semi-coiled. See Darnton, N.C., Turner, L., Rojevsky, S. and Berg, H.C. On torque and tumbling in swimming Escherichia coli, J. Bacteriol. 189, 1756-1764 (2007).'
Tumbling time	0.14±0.19s	AW405	Exponential distribution fitted (stated to be exponential by Berg and Brown) using only the mean tumble length (not STDEV).	[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking]
Relationship between tumbling angle and time
Speed while Tumbling	0μm.s^-1	AW405	Berg and Brown noted that AW405 slowed/stopped while tumbling.	[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking]
Drift during run	23±23°	AW405	Drift was observed. It is what would be expected from rotational diffusion. (at 2.7cp at 32ºC drift was 23±23°). Rotational Brownian motion cause the cell to veer off course, so that in between tumbles the probability density function f of the swimming direction e evolves according to the Fokker-Planck equation. Drift velocity in steep gradient of attractant ~7 µm.s^-1(Berg & Turner, 1990. Note our model did not include the effects of drift	[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking] [http://www.springerlink.com/content/d8u27q8430202342/ Persistence of direction increases the drift velocity of run and tumble chemotaxis] [http://www.pdn.cam.ac.uk/groups/comp-cell/Biophysics.html Bray computer modelling]
Thrust	Down an Asp gradient 0.41pN, Up an Asp gradient 0.4387pN	AW405	Average thrust =0.41pN. In the Berg and Brown paper it states that the speed of the bacteria up an aspartate chemotactic gradient increases by 7%. Therefore in our model we shall use the following; thrust DOWN the Asp gradient =0.41pN, up the Asp gradient = 0.4387pN. Data was obtained from 32 AW405s, a strain which has provided the majority of our previous parameters but is not as motile as MG1655. The value was obtained at 23ºC in viscosity 0.93 and 3.07 cP for motility buffer and motility buffer with 0.18% methylcellulose, respectively. The standard deviation is not used as the speed is fixed at 50µm.s^-1 . 0.57pN is the average thrust generated in strain HCB30 (a non tumbling strain). The thrust value was obtained when the imposed flow (U) U=0 at 23ºC. O.41pN was calculated using the resistance force theory treating the flagellar bundle as a single filament. The body was assumed to be prolate elipsoid using values roughly similar to ours, 2μm for length and 0.86μm for diameter.	[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking] [http://jb.asm.org/cgi/reprint/189/5/1756.pdf On Torque and Tumbling in Swimming E. coli] [http://www.pnas.org/content/103/37/13712.full.pdf+html Swimming efficiency of bacterium E. coli.]
Isotropic run lengths	0.86±1.18s	AW405	Exponential distribution fitted, this is only an approximate and does not fit exactly (see fig.4 Berg and Brown) The standard deviation is the standard deviation of the mean and has not been used in the exponential distribution	[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking]
Run length UP Aspartate gradient	1.07±1.80s	AW405	Exponential distribution fitted, this is only an approximate and does not fit exactly (see fig.6, Berg and Brown). The standard deviation is the standard deviation of the mean and has not been used in the exponential distribution.	[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking] [http://parts2.mit.edu/wiki/index.php/University_of_California_San_Francisco_2006 UCSF wiki]
Run length DOWN Aspartate gradient	0.8±1.38s	AW405	Exponential distribution fitted, this is only an approximate and does not fit exactly (see fig.6, Berg and Brown) The standard deviation is the standard deviation of the mean and has not been used in the exponential distribution	[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking]
Viscosity	Viscosity of water is 1.002cP at 20°C	N/A	At present the medium being used by the lab is still be discussed. Currently though the medium most resembles water and therefore the water's viscosity value can be used. This allows us to assume that the medium is Newtonian (dilute aqueous medium that doesn’t contain long unbranched molecules such as methylcellulose or polyvinylpyrrolidone. Note that methlycellulose does not alter the run and tumble statistics, only bundle and motor rotation rates are affected by the addition of methylcellulose). If agar were to be used then the medium would be Non-Newtonian. Even though it would be Non- Newtonian John Hogan in passing said that we could assume it is Newtonian.	[http://arjournals.annualreviews.org/doi/pdf/10.1146/annurev.biochem.72.121801.161737 The rotary motor of bacterial flagella.], [http://jb.asm.org/cgi/reprint/189/5/1756.pdf On Torque and Tumbling in swimming Escherichia coli]

GRN Modelling

Parameter	Value	Description	Reference
C_pMax	Unknown (varied in the program)	Maximal CpxR protein concentration
k_Cp	0.075min^{-1^ESTIMATED}	Maximal transcription rate of pCpxR promoter	[http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=11830644 Surface Sensing and Adhesion of Escherichia Coli controlled by the cpx-signalling pathway.]
theta_Cpx	1 x 10^-9 M ESTIMATED	Threshold for pCpxR promoter Hill Function	iGEM 2008 KULeuven
m_Cpx	1.0	Co-operativity of pCpxR promoter Hill function
d_Im	3.6 x 10^-1 min^-1	Degradation rate of GFP mRNA	[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347 Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
k_Ip	9.6 x 10^-1 min^-1	Rate of LuxI protein translation	[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347 Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
d_Ip	1.67 x 10^-2 min^-1	Degradation rate of LuxI protein	[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347 Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
d_Gm	1.65 x 10^-3 min^-1	Degradation rate of GFP protein	[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T36-42HFN5W-11&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000010018&_version=1&_urlVersion=0&_userid=121739&md5=38be996fd7eb7dc4e71179e9d721b298 Efficient GFP mutations profoundly affect mRNA transcription and translation rates ]
k_Gp	2.4 x 10^-1 min^-1	Rate of GFP protein translation	[http://www.springerlink.com/content/p14488p56p37n602/ Quantitative measurement of green fluorescent protein expression]
d_Gp	2.14 x 10^-4 min^-1	Degradation rate of GFP protein	[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347 Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
A_prod	3.6 min^-1	AHL production rate per LuxI enzyme	[[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347 Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
d_A	1 x 10^-2 min^-1	Degradation rate of AHL molecule	[http://www.nature.com/nature/journal/v434/n7037/full/nature03461.html A synthetic multicellular system for programmed pattern formation ]
D_A	0.23s^-1	Diffusion coefficient of AHL	[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347 Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
k_Tp	0.08min^-1	Maximal Transcription rate of ptetR promoter	iGEM 2007Imperial College London
d_Rm	3.6 x 10^-1 min^-1	Degradation rate of LuxR mRNA	[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347 Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
k_Rp	9.6 x 10^-1 min^-1	Rate of Lux protein translation	[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347 Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
d_Rp	2.31 x 10^-2 min^-1	Degration rate of LuxR protein	[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347 Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
k_LuxR	0.11 min^-1	Maximal transcription rate of LuxR promoter	iGEM 2008 KULeuven
theta_LuxR	1.5 x 10^-9 M	Threshold for LuxR pR promoter Hill function	iGEM 2008 KULeuven
m_LuxR	1.6	Co-operativity of LuxpR promoter Hill function	iGEM 2008 KULeuven
rho_C	0.5 micro M^-3 min^-1	LuxR/AHL dimerisation	[http://www.nature.com/nature/journal/v434/n7037/full/nature03461.html A synthetic multicellular system for programmed pattern formation ]
d_C	0.0231 min^-1	Degradation rate of mCherry mRNA	[http://www.nature.com/nature/journal/v434/n7037/full/nature03461.html A synthetic multicellular system for programmed pattern formation ]
d_Mm	1.65 x 10^-3 min^-1	Degradation rate of LuxR/AHL complex	Due to difficulty in finding mCherry modelling parameters, exsisting GFP parameters have been used.
k_Mp	2.4 x 10^-1 min^-1	Rate of mCherry protein translation	Due to difficulty in finding mCherry modelling parameters, exsisting GFP parameters have been used.
d_Mp	2.14 x 10^-4 min^-1	Degradation rate of mCherry protein	Due to difficulty in finding mCherry modelling parameters, exsisting GFP parameters have been used.

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 * [[Team:BCCS-Bristol/Modeling-Parameters#Bacteria|'''Bacteria''']]
-* [[Team:BCCS-Bristol/Modeling-Parameters#Run Tumble motion|'''Run Tumble motion''']]
+* [[Team:BCCS-Bristol/Modeling-Parameters#Run_Tumble_Motion|'''Run Tumble motion''']]
-* [[Team:BCCS-Bristol/Modeling-Parameters#Swimming Machinery|'''Swimming Machinery''']]
+* [[Team:BCCS-Bristol/Modeling-Parameters#GRN_Modelling|'''GRN Modelling''']]
-* [[Team:BCCS-Bristol/Modeling-Parameters#Properties of the media|'''Properties of the media''']]
+=== Bacteria ===
-=== Bacteria ===
+{| class="bccstable" align="center"  margin-left="40px"
-<br>
-{| {{table}} width="90%" align="center"
 | align="center" width="10%" style="background:#f0f0f0;"|'''Attribute'''
 | align="center" width="10%" style="background:#f0f0f0;"|'''Value'''
@@ Line 34: / Line 32: @@
 | align="center" width="30%" style="background:#f0f0f0;"|'''Reference'''
 |-
-| Length||2ìm||MG1655||Values come from the University of Alberta’s datasheet on MG1655, produced to aid modelling. There is variability in size between strains - for instance, AW405 length varies between 1.5±0.2ìm. But University of Alberta datasheet is specifically for MG1655.||[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
+| Length||2&#956;m||MG1655||Values come from the University of Alberta’s datasheet on MG1655, produced to aid modelling. There is variability in size between strains - for instance, AW405 length varies between 1.5±0.2&#956;m. But University of Alberta datasheet is specifically for MG1655.||[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
 |-
-| Diameter||0.8ìm||MG1655||||[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
+| Diameter||0.8&#956;m||MG1655||||[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
 |-
-| Shape||Circle r =0.714ìm||MG1655||Actually rod-like. A circle with r= 0.714ìm will have equivalent surface area to rod-like.||[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
+| Shape||Circle r =0.714&#956;m||MG1655||Actually rod-like. A circle with r= 0.714&#956;m will have equivalent surface area to rod-like.||[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
 |-
-| Mass||1.02x10-13g||MG1655||Given 1x10-12g for cell wet weight. Dividing this by gravity (=9.81) gives mass. ||[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
+| Mass||1.02x10<sup>-13</sup>g||MG1655||Given 1x10<sup>-12</sup>g for cell wet weight. Dividing this by gravity (=9.81) gives mass. ||[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta]
 |-
-| Swimming Speed||50ìm.s-1||MG1655||University Alberta's datasheet gives 50ìms-1. However, Swimming speed is affected by:
+| Swimming Speed||50&#956;ms<sup>-1</sup>||MG1655||University Alberta's datasheet gives 50&#956;ms<sup>-1</sup>. However, Swimming speed is affected by:
-*Viscosity (as viscosity increases the speed increases to some maximum, then decreases as the viscosity increases further. E.coli (strain:KL227 of length: 1.0ìm and diameter: 0.5ìm) maximum speed occurs at viscosity 8cp. Suggested to be because higher viscosity provides increased energy supply.
+*Viscosity (as viscosity increases the speed increases to some maximum, then decreases as the viscosity increases further. E.coli (strain:KL227 of length: 1.0&#956;m and diameter: 0.5&#956;m) maximum speed occurs at viscosity 8cp.
 *Temperature
 *Culture medium
 *Vary strain to strain.
 *Experimental methods
-Many papers give different and variable speeds (mainly for AW405 ~20ìms-1). The speed itself is nearly uniform during the run. May need to measure experimentally, don't know under what conditions University of Alberta. Alberta value is higher than other values, but probably because MG1655 is a motile strain.
+Various papers give different speeds for E. coli (most papers provide information on AW405 with a speed of ~20&#956;ms<sup>-1</sup>). The speed itself is nearly uniform during the run. The wet lab may need to measure this experimentally as we are unaware of the conditions that the speed for MG1655 was obtained. Alberta's value is higher than other values, but this probably because MG1655 is a motile strain.
-||[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta], [http://www3.interscience.wiley.com/cgi-bin/fulltext/71003069/PDFSTART A Method for Measuring Bacterial Chemotaxis Parameters in a Microcapillary]
+||[http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi University of Alberta] <br> [http://www3.interscience.wiley.com/cgi-bin/fulltext/71003069/PDFSTART A Method for Measuring Bacterial Chemotaxis Parameters in a Microcapillary]
-|-
-|
 |}
-=== Run Tumble motion  ===
+=== Run Tumble Motion ===
-{| {{table}}
+{| class="bccstable"
 | align="center" width="10%" style="background:#f0f0f0;"|'''Attribute'''
 | align="center" width="10%" style="background:#f0f0f0;"|'''Value'''
@@ Line 62: / Line 59: @@
 | align="center" width="30%" style="background:#f0f0f0;"|'''Reference'''
 |-
-| Aspartate concentration detected by E. coli||Over ~5 orders of magnitude, 10nM up to 10mM. Can detect changes of as little as ~0.1%||N/A||Most computer simulations of the chemotaxis pathway based on experimentally determined rates and concentrations predict a minimum detectable concentration of the attractant aspartate of around 200 nM. However, experiments performed by Segall et al. in 1986, in which E. coli cells are tethered to a coverslip were exposed to small quantities of chemoattractant delivered iontophoretically. These experiments indicated that a change in receptor occupancy of as little as 1/600 could produce an detectable change in swimming behaviour. With a Kd of 1 µM, this corresponds to a minimum detectable concentration of about 2 nM aspartate. E. coli cells can adapt to Aspartate concentrations over ~5 orders of magnitude.  Wild type E. coli cells can detect <10nM of Asp and respond to gradients upto 1mM of Asp. detect small changes in concentration ( 0.1%) via temporal comparisons ( 4 s) over a large range ( 10-8 to 10-3 M)||[http://www.jbc.org/cgi/reprint/281/41/30512 Competitive and Cooperative Interactions in Receptor Signalling Complexes]
+| Aspartate concentration detected by E. coli||Over ~5 orders of magnitude, 10nM up to 10mM. Can detect changes of as little as ~0.1%||N/A||E. coli detect small changes in concentration of 0.1% via temporal comparisons (4s) over a large range ( 10<sup>-8</sup> to 10<sup>-3</sup> ). Most computer simulations of chemotaxis are based on experimentally determined rates and concentrations. As a result they predict that the minimum detectable concentration of Aspartate is at ~200 nM. Experiments performed by Segall et al. in 1986, exposed tethered E. coli cells to iontophoretically delivered quantities of chemoattractant. These experiments indicated that a change in receptor occupancy of as little as 1/600 could produce an detectable change in swimming behaviour. With a K<sub>d</sub> of 1 µM, this corresponds to a minimum detectable concentration of about 2 nM Aspartate. Wild type E. coli cells can detect <10nM of Asp and respond to Asp concentrations of upto 1mM,(responding to over ~5 orders of magnitude). M)||[http://www.jbc.org/cgi/reprint/281/41/30512 Competitive and Cooperative Interactions in Receptor Signalling Complexes]
 |-
-| Temporal comparison of chemotactic gradient||4 seconds||N/A||The past second has positive weighting, the previous 3 seconds have negative weighting. E coli compares these concentrations (average occupancy of the receptors) and therefore the memory lasts approximately 3 s. Models reflecting this have been developed by Segall et al and Schnitzer, cells compare their average receptor occupancy between 4 and 1 s ago  c 1–4 to the average receptor occupancy during the last second  c 0–1. Hence b= c 0–1 -  c 1–4,  If b>0, the cell reduces the tumbling rate to Ttumb from the ambient value T0 (1s-1) e.g. b>0 don't tumble. b< tumble at a rate of 1s-1||[http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=387059&blobtype=pdf Temporal comparisons in bacterial chemotaxis] [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TBN-4CVRC68-2&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=470c7fd73fb9ebf4ca43342f365e221f#sec5.1 Quantitative analysis of signalling networks][http://web.mit.edu/biophysics/papers/PNAS2003b.pdf Motility of Escherichia coli cells in clusters formed by chemotactic aggregation]
+| Temporal comparison of chemotactic gradient||4 seconds||N/A||The past second has positive weighting, the previous 3 seconds have negative weighting. E coli compares past and present concentrations by comparing the average occupancy of the receptors over the 4s. Models reflecting this system have been developed by Segall et al and Schnitzer, cells compare their average receptor occupancy between 4 and 1 s ago  c<sub>1-4</sub> to the average receptor occupancy during the last second  c<sub>0-1</sub> . Hence b= c<sub>0-1</sub>  -  c<sub>1-4</sub> .   If b>0, the cell reduces the tumbling rate to T<sub>tumbling</sub> from the ambient value T<sub>0</sub> , 1s<sup>-1</sup> e.g. b>0 don't tumble. b< 0, tumble at a rate of 1s<sup>-1</sup> ||[http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=387059&blobtype=pdf Temporal comparisons in bacterial chemotaxis]<br> [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TBN-4CVRC68-2&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=470c7fd73fb9ebf4ca43342f365e221f#sec5.1 Quantitative analysis of signalling networks] <br> [http://web.mit.edu/biophysics/papers/PNAS2003b.pdf Motility of Escherichia coli cells in clusters formed by chemotactic aggregation]
 |-
-| Tumbling angle||Shape parameter 4 Scale parameter 18.32 Location parameter -4.6||AW405||Appears not to be dependant on the concentration gradient of chemoattractants/repellents. Nor is there correlation between the length of the run and the change in direction. Used a gamma distribution that fitted the data of Berg and Brown. Non normality observed by several groups. Suggestions that non-normality was only due to the experimental methods used e.g. in the capillary tube. Tumbling can cause a change in direction when as few as one filaments moves out of the bundle. The flagella on transition from the bundle to release go from normal (a left-handed helix with a pitch of 2.3  m and a diameter of 0.4  m) to semi coiled (a right-handed helix with half the normal pitch but normal amplitude) and then curly (a right-handed helix with half the normal pitch and half the normal amplitude).||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. coli anaylsed by three-dimensions] [http://bioinformatics.oxfordjournals.org/cgi/reprint/21/11/2714 AgentCell: a digital single-cell assay for bacterial chemotaxis] [http://jb.asm.org/cgi/reprint/189/5/1756 On Torque and tumbling in swimming Escherichia coli]||
+| Tumbling angle||Shape parameter 4 Scale parameter 18.32 Location parameter -4.6||AW405||The tumble angle appears not to be dependant on the concentration gradient of chemoattractants/repellents. Nor is there correlation between the length of the run and the change in direction. The program uses a gamma distribution that fits the data collected by Berg and Brown. Several groups though, have observed that the tumble angle is not noramlly distributed but suggest that non-normality was only due to the experimental methods used e.g. in the capillary tube. Tumbling can cause a change in direction when as few as one flagella moves out of the bundle. ||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. coli anaylsed by three-dimensions] <br> [http://bioinformatics.oxfordjournals.org/cgi/reprint/21/11/2714 AgentCell: a digital single-cell assay for bacterial chemotaxis] <br> [http://jb.asm.org/cgi/reprint/189/5/1756 On Torque and tumbling in swimming Escherichia coli]
 |-
-| Tumble angle direction||Bidirectional||AW405||Personal communication with Howard Berg. 'The direction is random, more or less, but there is a slight forward bias. It varies from tumble to tumble.  The turn-angle distribution peaks at 68 deg rather than 90 deg. Tumbles turn out to be more complex than believed in 1972.  Motors switch independently, and a tumble can occur if one or just a few motors change their directions of rotation.  Tumbles are short, as judged by the tracking microscope, because they involve filament physics rather than motor physics:  a transformation in polymorphic form, following motor reversal, from normal to semi-coiled.  See  Darnton, N.C., Turner, L., Rojevsky, S. and Berg, H.C.  On torque and tumbling in swimming Escherichia coli, J. Bacteriol. 189, 1756-1764 (2007).'
+| Tumble angle direction||Bidirectional||AW405||Personal communication with Howard Berg. 'The direction is random, more or less, but there is a slight forward bias. It varies from tumble to tumble.  The turn-angle distribution peaks at 68° rather than 90°. Tumbles turn out to be more complex than believed in 1972.  Motors switch independently, and a tumble can occur if one or just a few motors change their directions of rotation.  Tumbles are short, as judged by the tracking microscope, because they involve filament physics rather than motor physics:  a transformation in polymorphic form, following motor reversal, from normal to semi-coiled.  See  Darnton, N.C., Turner, L., Rojevsky, S. and Berg, H.C.  On torque and tumbling in swimming Escherichia coli, J. Bacteriol. 189, 1756-1764 (2007).'||
 |-
 | Tumbling time||0.14±0.19s||AW405||Exponential distribution fitted (stated to be exponential by Berg and Brown) using only the mean tumble length (not STDEV).||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking]
@@ Line 74: / Line 71: @@
 | Relationship between tumbling angle and time||||||||
 |-
-| Speed while Tumbling||0μm.s-1||AW405||Berg and Brown noted that AW405 slowed/stopped while tumbling.||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking]
+| Speed while Tumbling||0μm.s<sup>-1</sup>||AW405||Berg and Brown noted that AW405 slowed/stopped while tumbling.||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking]
 |-
-| Drift during run||23±23○||AW405||Drift was observed. It is what would be expected from rotational diffusion. (at 2.7cp at 32ºC drift was 23±23°). Rotational Brownian motion cause the cell to veer off course, so that in between tumbles the probability density function f of the swimming direction e evolves according to the Fokker-Planck equation.   Drift velocity in steep gradient of attractant ~7 µm/s (Berg & Turner, 1990)||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking] [http://www.springerlink.com/content/d8u27q8430202342/ Persistence of direction increases the drift velocity of run and tumble chemotaxis] [http://www.pdn.cam.ac.uk/groups/comp-cell/Biophysics.html Bray computer modelling]
+| Drift during run||23±23°||AW405||Drift was observed. It is what would be expected from rotational diffusion. (at 2.7cp at 32ºC drift was 23±23°). Rotational Brownian motion cause the cell to veer off course, so that in between tumbles the probability density function f of the swimming direction e evolves according to the Fokker-Planck equation.   Drift velocity in steep gradient of attractant ~7 µm.s<sup>-1</sup>(Berg & Turner, 1990. Note our model did not include the effects of drift||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking] <br> [http://www.springerlink.com/content/d8u27q8430202342/ Persistence of direction increases the drift velocity of run and tumble chemotaxis] <br>  [http://www.pdn.cam.ac.uk/groups/comp-cell/Biophysics.html Bray computer modelling]
+|-
+| Thrust||Down an Asp gradient 0.41pN, Up an Asp gradient 0.4387pN ||AW405||Average thrust =0.41pN. In the Berg and Brown paper it states that the speed of the bacteria up an aspartate chemotactic gradient increases by 7%. Therefore in our model we shall use the following; thrust DOWN the Asp gradient =0.41pN, up the Asp gradient = 0.4387pN. Data was obtained from 32 AW405s, a strain which has provided the majority of our previous parameters but is not as motile as MG1655. The value was obtained at 23ºC in viscosity 0.93 and 3.07 cP for motility buffer and motility buffer with 0.18% methylcellulose, respectively. The standard deviation is not used as the speed is fixed at 50µm.s<sup>-1</sup> . 0.57pN is the average thrust generated in strain HCB30 (a non tumbling strain). The thrust value was obtained when the imposed flow (U) U=0 at 23ºC. O.41pN was calculated using the resistance force theory treating the flagellar bundle as a single filament. The body was assumed to be prolate elipsoid using values roughly similar to ours, 2μm for length and 0.86μm for diameter. ||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking] <br> [http://jb.asm.org/cgi/reprint/189/5/1756.pdf On Torque and Tumbling in Swimming E. coli]<br> [http://www.pnas.org/content/103/37/13712.full.pdf+html Swimming efficiency of bacterium E. coli.]
 |-
 | Isotropic run lengths||0.86±1.18s||AW405||Exponential distribution fitted, this is only an approximate and does not fit exactly (see fig.4 Berg and Brown) The standard deviation is the standard deviation of the mean and has not been used in the exponential distribution||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking]
 |-
-| Run length UP Aspartate gradient||1.07±1.80s||AW405||Exponential distribution fitted, this is only an approximate and does not fit exactly (see fig.6, Berg and Brown). The standard deviation is the standard deviation of the mean and has not been used in the exponential distribution Phenylalanine ( the recruitment chemoattractant) utilises a mutant of the Tar receptor. The mutant Tar receptor has been shown to have comparable chemotactic response to the wild type and therefore the values used for the run lengths of aspartate can also be used for phenylalanine.||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking][http://parts2.mit.edu/wiki/index.php/University_of_California_San_Francisco_2006 UCSF wiki]
+| Run length UP Aspartate gradient||1.07±1.80s||AW405||Exponential distribution fitted, this is only an approximate and does not fit exactly (see fig.6, Berg and Brown). The standard deviation is the standard deviation of the mean and has not been used in the exponential distribution. ||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking] <br> [http://parts2.mit.edu/wiki/index.php/University_of_California_San_Francisco_2006 UCSF wiki]
 |-
 | Run length DOWN Aspartate gradient||0.8±1.38s||AW405||Exponential distribution fitted, this is only an approximate and does not fit exactly (see fig.6, Berg and Brown) The standard deviation is the standard deviation of the mean and has not been used in the exponential distribution||[http://www.nature.com/nature/journal/v239/n5374/pdf/239500a0.pdf Chemotaxis in E. Coli anaylsed by three-dimensional tracking]
 |-
-|
+| Viscosity||Viscosity of water is 1.002cP at 20°C||N/A||At present the medium being used by the lab is still be discussed. Currently though the medium most resembles water and therefore the water's viscosity value can be used. This allows us to assume that the medium is Newtonian (dilute aqueous medium that doesn’t contain long unbranched molecules such as methylcellulose or polyvinylpyrrolidone. Note that methlycellulose does not alter the run and tumble statistics, only bundle and motor rotation rates are affected by the addition of methylcellulose). If agar were to be used then the medium would be Non-Newtonian. Even though it would be Non- Newtonian John Hogan in passing said that we could assume it is Newtonian.||[http://arjournals.annualreviews.org/doi/pdf/10.1146/annurev.biochem.72.121801.161737 The rotary motor of bacterial flagella.],  [http://jb.asm.org/cgi/reprint/189/5/1756.pdf On Torque and Tumbling in swimming Escherichia coli]
+|-
 |}
-=== Swimming Machinery ===
+=== GRN Modelling ===
-{| {{table}}
+{| class="bccstable"
-| align="center" width="10%" style="background:#f0f0f0;"|'''Attribute'''
+| align="center" width="10%" style="background:#f0f0f0;"|'''Parameter'''
-| align="center" width="10%" style="background:#f0f0f0;"|'''Value'''
+| align="center" width="20%" style="background:#f0f0f0;"|'''Value'''
-| align="center" width="10%" style="background:#f0f0f0;"|'''Strain'''
+| align="center" width="40%" style="background:#f0f0f0;"|'''Description'''
-| align="center" width="40%" style="background:#f0f0f0;"|'''Justification'''
 | align="center" width="30%" style="background:#f0f0f0;"|'''Reference'''
 |-
-| Average thrust ||0.41±0.23 pN||AW405||0.41±0.23 pN ( standard deviation for 32 bacteria) was obtained from strain AW405, a strain which has provided the majority of our previous parameters but is not MG1655 which is more motile. The value was obtained at 23ºC in viscosity 0.93 and 3.07 cP for motility buffer and motility buffer with 0.18% methylcellulose, respectively. The standard deviation is not used as the speed is fixed at 50µm/s. 0.57pN is the average thrust generated in strain HCB30 (a non tumbling strain). The thrust value was obtained when the imposed flow (U) U=0 at 23ºC. O.41pN was calculated using the resistance force theory treating the flagellar bundle as a single filament. The body was assumed to be prolate elipsoid using values roughly similar to ours, 2μm for length and 0.86μm for diameter.||[http://jb.asm.org/cgi/reprint/189/5/1756 On Torque and tumbling in swimming Escherichia coli] [http://www.pnas.org/content/103/37/13712.full.pdf+html Swimming efficiency of bacterium E. coli.]
+| C<sub>pMax<sub> ||Unknown (varied in the program)||Maximal CpxR protein concentration||||
 |-
-|
+| k<sub>Cp<sub> ||0.075min<sup>-1<sup> <br> ESTIMATED ||Maximal transcription rate of pCpxR promoter || [http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=11830644 Surface Sensing and Adhesion of Escherichia Coli controlled by the cpx-signalling pathway.]
-|}
-===Properties of the media===
-{| {{table}}
-| align="center" width="10%" style="background:#f0f0f0;"|'''Attribute'''
-| align="center" width="10%" style="background:#f0f0f0;"|'''Value'''
-| align="center" width="10%" style="background:#f0f0f0;"|'''Strain'''
-| align="center" width="40%" style="background:#f0f0f0;"|'''Justification'''
-| align="center" width="30%" style="background:#f0f0f0;"|'''Reference'''
 |-
-| Viscosity||Viscosity of water is 1.002cP at 20○C||N/A||At present the medium being used by the lab is still be discussed. Currently though the medium most resembles water and therefore the water's viscosity value can be used. This allows us to assume that the medium is Newtonian (dilute aqueous medium that doesn’t contain long unbranched molecules such as methylcellulose or polyvinylpyrrolidone. Note that methlycellulose does not alter the run and tumble statistics, only bundle and motor rotation rates are affected by the addition of methylcellulose). If agar were to be used then the medium would be Non-Newtonian. Even though it would be Non- Newtonian John Hogan in passing said that we could assume it is Newtonian.||[http://arjournals.annualreviews.org/doi/pdf/10.1146/annurev.biochem.72.121801.161737 The rotary motor of bacterial flagella. Physica A 358 (2005) 205–211.]  On torque and tumbling in swimming Escherichia coli
+| theta<sub>Cpx<sub> ||1 x 10<sup>-9</sup> M <br> ESTIMATED ||Threshold for pCpxR promoter Hill Function || [https://2008.igem.org/team:kuleuven iGEM 2008 KULeuven ]||
 |-
-| Diffusion coefficient of Aspartate.||0.033 cm2.h-1||N/A||0.033 cm2/h is for aspartate at 22°C in 0.15% agar. Another value from the literature, 0.9 x10-5 cm2/s, is for aspartate at 35◦C in 0.3% agar. To calculate diffusion coefficients the following formula can be used D=RT/6πNvr where: R is the gas constant, T is the absolute temperature (Kelvin), N is the number of molecules in a mole (6 x1023), v is the viscosition of the solvent (e.g. 0.001 for water), r= radius of the particle. This formula could be used to calculate the diffusion coefficient at the viscosity used in our experiments.||[http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=1300146&blobtype=pdf Chemotactic Responses of Escherichia coli to Small Jumps of Photoreleased L-Aspartate] [http://www.pnas.org/content/96/20/11346.full.pdf\" Response tuning in bacterial chemotaxis]
+| m<sub>Cpx<sub> ||1.0 || Co-operativity of pCpxR promoter Hill function ||||
 |-
-| Diffusion coefficient of Phenylalanine.||3.58 x 10-4 cm 2 min -1||N/A||This value is for phenylalanine in aqueous phase at 25ºC. ||[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TGK-3W38497-D&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000010018&_version=1&_urlVersion=0&_userid=121739&md5=316e71596cb388d2a0cf0de7c15f84fe#fd16 Extraction and re-extraction of phenylalanine by cationic reversed micelles in hollow fibre contactors]
+| d<sub>Im<sub> || 3.6 x 10<sup>-1</sup>  min<sup>-1<sup> || Degradation rate of GFP mRNA ||[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347      Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
 |-
-| Quorum Signal||OHHL (3-oxo-C6-HSL)||N/A||From the quorum sensing system of Vibrio Fischeri produced by LuxI. Molecular weight: 213||
+| k<sub>Ip<sub> || 9.6 x 10<sup>-1</sup>  min<sup>-1<sup> || Rate of LuxI protein translation || [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347      Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
 |-
-| Basal (constitutive) rate of AHL production||30nmol.hr-1||V. fischeri||Value was used in a modelling simulation of the Lux system in V. fischeri. Note that the maximum [AHL] is achieved during stationary phase.||[http://docstore.ingenta.com/cgi-bin/ds_deliver/1/u/d/ISIS/45421751.1/ap/mb/2001/00000309/00000003/art04697/34CECEE65ADECE1112181237349BDA2365FA8246B1.pdf?link=http://bristol.library.ingentaconnect.com/error/delivery&format=pdf Kinectics of the AHL regulatory system in a model biofilmsystem: How many bacteria constitute a Quorum?]
+| d<sub>Ip<sub> || 1.67 x 10<sup>-2</sup>  min<sup>-1<sup> || Degradation rate of LuxI protein || [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347      Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
 |-
-| Diffusion coefficient for Quorum signal||Daq= 4.9x 10-6 cm2 s-1||N/A||Daq= 4.9x10-6cm2.s-1 is the diffusion coefficient of 3 oxo-C12 AHL in water, not OHHL as we would be using. Estimations can be calculated using Wilke Chang equation (see Perry\'s Chemical Engineers\' Handbook). De = 1.23x 10-6 cm2 s-1 is the effective diffusion coefficient of 3 oxo-C12 AHL in biofilm. ||[http://www.springerlink.com/content/v36128k24t558820/fulltext.pdf The effect of the chemical, biological and physical environment on quorum sensing in structured microbial communities. Anal Bioanal Chem (2007) 387:371-380.]
+| d<sub>Gm<sub> || 1.65 x 10<sup>-3</sup> min<sup>-1<sup> || Degradation rate of GFP protein || [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T36-42HFN5W-11&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000010018&_version=1&_urlVersion=0&_userid=121739&md5=38be996fd7eb7dc4e71179e9d721b298 Efficient GFP mutations profoundly affect mRNA transcription and translation rates ]
 |-
-| Threshold concentration of autoinducer||Use imperial iGEM value 1nM!  ~1 to 10μg.ml-1||N/A||In the pattern formation paper fig 2c and d represent a simulation and experimental data respecitively. The graph plots the concentration of AHL required to elicit a visual response (observation of fluorescence). Imperial iGEM team looked at the lower and higher threshold levels of AHL in vivo and in vitro.  They also visualised this with expression of GFP. Low threshold 1nM in vivo (estimated the number of plasmids present) in vitro value is only obtained on extrapolation and therefore it is not accurate but predicited to be higher. High threshold is ~1000nM and therefore beyond this level the system does not respond to any further increase, the system is saturated. See graph sheet. Another paper, A novel strategy for the isolation of luxl homologues:evidence for the widespread distribution of a LuxR:Luxl superfamily in enteric bacteria. The V. fischeri sensor for OHHL is very senstive requiring levels of 10ng.ml-1  to inititate transcription. This paper also states that the thresholds differ depending on strain of bacteria and cell densities. The Imperial\'s iGEM team value is the best as it is for MC1000 and therefore most relevent for this project.||[http://www.nature.com/nature/journal/v434/n7037/pdf/nature03461.pdf A synthetic multicellular system for programmed pattern formation.] [http://parts.mit.edu/igem07/index.php/Imperial/Infector_Detector/F2620_Comparison Imperial iGEM wiki][http://www3.interscience.wiley.com/cgi-bin/fulltext/119307663/PDFSTART A novel strategy for the isolation of luxl homologues: evidence for the widespread distribution of a LuxR:Luxl superfamily in enteric bacteria]
+| k<sub>Gp<sub> || 2.4 x 10<sup>-1</sup> min<sup>-1<sup> || Rate of GFP protein translation || [http://www.springerlink.com/content/p14488p56p37n602/  Quantitative measurement of green fluorescent protein expression]
 |-
-| Protein decay (LuxR/AHL)||0.0231 min-1|||||| [http://www.nature.com/nature/journal/v434/n7037/pdf/nature03461.pdf A synthetic multicellular system for programmed pattern formation.]
+| d<sub>Gp<sub> || 2.14 x 10<sup>-4</sup> min<sup>-1<sup> || Degradation rate of GFP protein || [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347      Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
 |-
-| LuxR/AHL activation coefficient||0.01µM||||||[http://www.nature.com/nature/journal/v434/n7037/pdf/nature03461.pdf A synthetic multicellular system for programmed pattern formation.]
+| A<sub>prod<sub> || 3.6 min<sup>-1<sup> || AHL production rate per LuxI enzyme ||[[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347      Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
 |-
-| LuxR/AHL dimerisation ||0.5µM-3.min-1||||||[http://www.nature.com/nature/journal/v434/n7037/pdf/nature03461.pdf A synthetic multicellular system for programmed pattern formation.]
+| d<sub>A<sub> || 1 x 10<sup>-2</sup> min<sup>-1<sup> || Degradation rate of AHL molecule ||[http://www.nature.com/nature/journal/v434/n7037/full/nature03461.html A synthetic multicellular system for programmed pattern formation ]
 |-
-| AHL decay||0.01min-1||||Note that this value is affected by pH||[http://www.nature.com/nature/journal/v434/n7037/pdf/nature03461.pdf A synthetic multicellular system for programmed pattern formation.]
+| D<sub>A<sub> || 0.23s<sup>-1<sup> || Diffusion coefficient of AHL || [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347      Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
 |-
-| Particle||10µm diameter and round||||Value obtained from lab team||Bacterial flagella-based propulsion and on/off motion control of microscale objects
+| k<sub>Tp<sub> || 0.08min<sup>-1<sup> || Maximal Transcription rate of ptetR promoter || [https://2007.igem.org/Imperial/imperial/cell-free/characterisation iGEM 2007Imperial College London]
 |-
-| Particle density||1.05g.cm-3||N/A||Value is for the particles the lab team is using||
+| d<sub>Rm<sub> || 3.6 x 10<sup>-1</sup> min<sup>-1<sup> || Degradation rate of LuxR mRNA || [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347      Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
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-| Diffusion coefficient of 10μm polystyrene bead||4.93x10-14 m2/s||N/A||||Bacterial flagella-based propulsion and on/off motion control of microscale objects
+| k<sub>Rp<sub> || 9.6 x 10<sup>-1</sup> min<sup>-1<sup> || Rate of Lux protein translation || [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347      Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
 |-
-| Drag on 10μm sphere||1.4pN||N/A||||Bacterial flagella-based propulsion and on/off motion control of microscale objects
+| d<sub>Rp<sub> || 2.31 x 10<sup>-2</sup> min<sup>-1<sup> || Degration rate of LuxR protein ||[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4H4T39N-1&_user=121739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=121739&md5=08a37acb41420b0e80d3cde6ead4a347      Systems Analysis of a quorum sensing network: Design constraints imposed by the functional requirements, network topology and kinetic constants.]
 |-
-|
+| k<sub>LuxR<sub> || 0.11 min<sup>-1<sup> || Maximal transcription rate of LuxR promoter || [https://2008.igem.org/team:kuleuven iGEM 2008 KULeuven ]
+|-
+| theta<sub>LuxR<sub> || 1.5 x 10<sup>-9</sup> M || Threshold for LuxR pR promoter Hill function || [https://2008.igem.org/team:kuleuven iGEM 2008 KULeuven ]
+|-
+| m<sub>LuxR<sub> || 1.6 || Co-operativity of LuxpR promoter Hill function || [https://2008.igem.org/team:kuleuven iGEM 2008 KULeuven ]
+|-
+| rho<sub>C<sub> || 0.5 micro M<sup>-3</sup> min<sup>-1</sup> || LuxR/AHL dimerisation ||[http://www.nature.com/nature/journal/v434/n7037/full/nature03461.html A synthetic multicellular system for programmed pattern formation ]
+|-
+| d<sub>C<sub> || 0.0231 min<sup>-1<sup> || Degradation rate of mCherry  mRNA ||[http://www.nature.com/nature/journal/v434/n7037/full/nature03461.html A synthetic multicellular system for programmed pattern formation ]
+|-
+| d<sub>Mm<sub> || 1.65 x 10<sup>-3</sup> min<sup>-1<sup> || Degradation rate of LuxR/AHL complex ||Due to difficulty in finding mCherry modelling parameters, exsisting GFP parameters have been used. ||
+|-
+| k<sub>Mp<sub> || 2.4 x 10<sup>-1</sup> min<sup>-1<sup> || Rate of mCherry protein translation || Due to difficulty in finding mCherry modelling parameters, exsisting GFP parameters have been used. ||
+|-
+| d<sub>Mp<sub> || 2.14 x 10<sup>-4</sup> min<sup>-1<sup> || Degradation rate of mCherry protein || Due to difficulty in finding mCherry modelling parameters, exsisting GFP parameters have been used. ||
 |}
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