Those of us who paid a little attention in high school Biology know that Bacteria are present inside the human body in large numbers and have the evolutionary ability to move from one place to another with the help of flagella that are essentially long tails made of proteins, visible at a nano level. Now we know about these flaps, what controls their movements? Nano 3D imaging shows how each of them is controlled at a minute level by these amazing motors that are made of proteins as well and work at such a small level to help propel the bacterium forward.
Now bacterias vary from shapes to sizes and therefore, each motor functions differently in these unicellular organisms and therefore, their swimming power also changes. Campylobacter jejuni is a kind of bacteria that needs to propel in the gut to cause food poisoning. Now the semi-solid mixture there provides a rough medium to operate, but this bacteria can move powerfully and can efficiently do so in the harsh terrain around it.
These reasons of different kinds of swimming abilities have largely been unknown until recent times when scientists were able to perform experiments using the state-of-the-art electron microscope at Imperial College, London. A team of researchers led by Dr Morgan Beeby has been able to model these motors at an unprecedented level. These latest computer models show the differences in swimming ability and power in different kinds of motors available to bacteria. The findings were published in the famed Proceedings of National Academy of Sciences.
These motors work on a rotational mechanism that propels the flagella to produce a kind of helical motion that propels the whole organism forward. Just like any engineered motor, Bacteria can add to the power of the motor by adding extra parts and increasing the sheer size of it. It is is amazing to see the kind of engineering nature can do, even if it can make us sick!
While not all bacteria are particularly powerful swimmers, the purpose has been redefined for some entirely. Vibrio cholera, the bacteria that causes Cholera has only intermediate power in its motors and some are even weaker than that. Now studying this level of detail was no easy feat for the researchers to achieve. The bacteria was rapidly frozen to -180 degrees using electron cryotomography that prevents ice crystals from forming on the frozen material. Digital 3D imaging from a 360-degree view creates the 3-D imagery for the motors. Dr. Morgan is now working on finding out what kind of evolutionary conditions allowed the bacteria to evolve in such varying patterns. Pretty cool, isn’t it?
