Team:Glasgow/Modeling

From 2014.igem.org

(Difference between revisions)
Line 28: Line 28:
#randomgif {width:450px;}
#randomgif {width:450px;}
 +
 +
#dog {width:400px;}
Line 65: Line 67:
<img id="nochemo" class="allimage" src="https://static.igem.org/mediawiki/2014/0/07/GU_no_chemotaxis.PNG"/>
<img id="nochemo" class="allimage" src="https://static.igem.org/mediawiki/2014/0/07/GU_no_chemotaxis.PNG"/>
 +
<img id="chemo" class="allimage" src="https://static.igem.org/mediawiki/2014/1/19/GU_chemotaxic_gradient.PNG"/>
<img id="chemo" class="allimage" src="https://static.igem.org/mediawiki/2014/1/19/GU_chemotaxic_gradient.PNG"/>
<br>
<br>
Line 80: Line 83:
<img id="RWsteps" class="allimage"  src="https://static.igem.org/mediawiki/2014/b/b1/GU_random_walk_100_steps.jpg"/>
<img id="RWsteps" class="allimage"  src="https://static.igem.org/mediawiki/2014/b/b1/GU_random_walk_100_steps.jpg"/>
 +
<br>
 +
<br>
 +
<br>
 +
<br>
 +
<br>
 +
<br>
 +
<br>
 +
<br>
-
<img id="randomgif" class="allimage" src="https://static.igem.org/mediawiki/2014/3/39/GU_randomswim.gif"/>
+
<img id="randomgif" class="allimage" align="right" src="https://static.igem.org/mediawiki/2014/3/39/GU_randomswim.gif"/>
 +
<br>
<br>
<br>
<img id="dog" class="allimage" src="https://static.igem.org/mediawiki/2014/2/20/GU_Dog.jpg"/>
<img id="dog" class="allimage" src="https://static.igem.org/mediawiki/2014/2/20/GU_Dog.jpg"/>

Revision as of 15:27, 6 August 2014

Bubble Test Page








Click here to edit this page!



Section 1: Modelling of Bacteria Random Walk
Firstly, we created a very basic 2D model of a flagella propelled bacterium. This was heavily based on the “random walk” model we mentioned previously, only we introduced a small degree of order, based on a more extensive and all-encompassing model created by Dillon, Fauci and Gaver in 1995.(link to paper?)DOI: 10.1006/jtbi.1995.0251

In order to simplify the model, we made a number of assumptions. These are:
  • Tumbling is instantaneous
  • Chemotaxic gradient is not a factor
  • An E.coil cell can be represented as a sphere
  • Speed is constant (20ms-1)

The movement of a bacteria through a medium is described thus:
1. The bacteria is moving at a random angle at a certain speed.
2. After a certain time (the “run” time), the bacteria reorientates itself (the “tumble”),
and sets off at a different angle. This run time can be influenced by the chemotaxic gradient,
if present.

The images below describe how the run times are influenced: if the bacteria is on a path towards the "food", it is unlikely to change direction.









Based on the previous research, we decided that the tumble angle would be picked each time from a normal distribution, having a mean of 68 degrees and a standard deviation of 36. This angle would be either added or subtracted from the previous position. The speed was set at a constant 20ms-1.Given angle, speed and time, new x and y coordinates are calculated and plotted. This process is repeated for any number of steps to show the theoretical path of a bacterium.











And here's random walk run that happened to look like a dog