Team:Goettingen/week10-1

V07_03

• Experiment:
  The cells are dropped onto M9-medium, that are prepared with a 0.5% trypton solution soaked whatman paper. The used strains are DH10B, DH5alpha, XL1, and BL21, each in four variations (empty vector, 18C-, 18O-, 18M-vector)
• Observations & Results:
  On the next day, there was no swimming visible at all. After two more (three in total) days, there was strong swimming for the BL21 strains detectable. ∆tar and DH10B strains showed minimal, DH5alpha and XL1 no swimming

• Experiment:
  The swimming assay was performed with ∆tar strains (with empty vector, 18C, and 18M) on M9 agar. For the whatman paper a variety of solutions was tested: Asp+Met, Asp+Leu, Asp+Leu+Met, Trypton, H₂0. Each solution was used in two different variations, w/ and w/o fluorescin to detect its diffusion over the agar plate.
• Observations & Results:
  On the next day, none of the plates showed any swimming. Also, the fluorescin concentration must have been to low, because no fluorescence was detectable under UV light.

V07_05

• Experiment:
  Wild-type strains without any transformed plasmids were dropped onto M9 agar plates, to identify those that are sensitive for the used chemoattractants (0.5% trypton solution and 50 mM aspartate solution). The chemoattractant was incoroporated into the Whatman paper, which was put in the middle of the agar plate. Furthermore, the influence of chemotaxis-washing-buffer was tested. The approach from above was done twice, once w/ and once w/o a washing step.