In this study we modelled and measured the U-turn trajectories of individual
magnetotactic bacteria under the application of rotating magnetic fields,
ranging in ampitude from 1 to 12 mT. The model is based on the balance between
rotational drag and magnetic torque. For accurate verification of this model,
bacteria were observed inside 5 m tall microfluidic channels, so that they
remained in focus during the entire trajectory. From the analysis of hundreds
of trajectories and accurate measurements of bacteria and magnetosome chain
dimensions, we confirmed that the model is correct within measurement error.
The resulting average rate of rotation of Magnetospirillum Gryphiswaldense is
0.74 +- 0.03 rad/mTs.Comment: 17 pages, 12 figure