This pumping “bacterial heart” is made from a type of photosynthetic cyanobacterium called Oscillatoria animalis which is named after the unique oscillatory nature of the movement of its cells. It forms very long microscopic filaments, which move by sliding over each other, and which are also able to weave themselves into dense mats.
I’ve been experimenting with this bacterium for a while now and investigating its possible use as a sustainable BioTextile, as the bacterium needs just sunlight and air to grow. In one of my experiments, I had carefully nurtured a beautiful green and dense mat of the bacteria, and was really pissed off when I accidentally knocked the culture flask onto the floor. The plastic flask survived, but my precious cyanobacterial mat had broken up completely to form a dispersed green bacterial soup. I picked the flask up, placed it back on the lab bench, and then went for a much needed coffee. When I returned to the lab, 30 minutes later, and went back to the flask, to my amazement the mat of Oscillatoria had miraculously reformed, and in some manner the bacteria must have contracted and reorganised to reform their original shape.
The bacterial heart in this video, shows this phenomenon in time-lapse (speeded up from a13 minutes). I really don’t know whether this has been observed before, but the bacterial mass here is behaving collectively and contracting much like our own muscle tissue does. Can this mechanism be utilised to make bacterial muscles for microscopic devices or self-repairing forms? Can it be harnessed to generate electricity? In more wild speculation, could this contractive mechanism be the evolutionary origin of our own muscle tissue through some endosymbiotic process? Science from art.
The motion of the bacteria as viewed under a DIC microscope