Pressure controlled micro-manipulation of bioluminescent microorganisms
Micropipetting was proved to be a useful and easy technique to hold highly motile organisms like the green algae Chlamydomonas rheinhardtii or Volvox in order to study their behavior and their swimming mechanisms. We aim to implement a new micropipette system not only to hold a microorganism, but also to be able to actuate it mechanically. In particular, we are interested in using this method to study the response of a bioluminescent organism to deformation and also light. Such a system requires a highly sensitive pressure and motion control of the micro-pipette. We will construct a custom-made Arduino-controlled device, a pressure-controlled pump for the micropipettes in order to mechanically stimulate the organism via two mechanisms: 1. With controlling the pressure of the flow inside the micro-pipettes, we hold the organism from its two ends. 2. Using adjustable arms that are connected to the linear motors, we deform (push and pull) the microorganisms in a controlled fashion. The optical response (bioluminescence) will be captured microscopically. Moreover, we will use the same micropipette holding system to study the response of the single organisms to light stimuli. To study their immediate response to these light-stimuli, the onset of the laser irradiation will trigger a high-speed camera.