"
Team:Heidelberg/Notebook/Visualization/Notebook/SwarmAssays
From 2008.igem.org
Swarm Assays
STARTED 2008-09-27
PURPOSE:
Test of the abbility of strains expressing the fusion receptor, to move against an attractant gradient.
STRAIN:
As autoinducer 2 producing attactant strain DH5α was used.
The fusion receptor plasmid was further cloned into HCB33 and UU1250 strains.
METHOD:
Petri-dishes were used es running chambers.
A petri-dish was filled with a media containig agar. Then the attractant was spotted on premarked positions or spotted as a line through the center of the petri-dish. After the gradient of the attractant has etablished the strains whioch should be attracted by the attractant where also set on premarked positions. The whole petri-dish was incubated at 37 °C and pictures were taken after 24, 48 and 72 hours.
For a more detailed protocol visit the Methods page.
A few pictures which have been taken during these experiments can be viewed under Projects and methods.
First swarm plates
A swarm assay test in 4 swarm plates was prepared.
2 different fusion constructs were used. Each in HCB33 and in UU1250.
Every petri-dish was filled with 20 ml of media. Two with minimal media containing about 0.3 % agar and the other two with TB media containing 0.2 % agar.
On a center line of both minimal plates and on one of the TB plates two spots of DH5α were created.
Afterwards fusion contruct 1 containing bacteria HCB33 and UU1250 were each spotted on the right half with an equal distance to the attractant spots. The same was done with the fusion construct 2 containing bacteria strains, but on the other half of the plate.
Up to now
Further swarm plates have been prepared testing different media and increasing the volume to 25 ml. A new spotting method of the attractant has been used by creating an attractant line through the center of the petri-dish.
So up to now a general protocol with which further swarm assys can be created step by step has been established.
The latest protocol can be viewed under the topic of swarm assays on Methods.
back to the visualization notebook
