Bacteria (or bacterium in singular) is a large domain of micrometer-long organisms that exist in different shapes ranging from rods, spheres, and spirals. They are believed to have been among the earliest life forms on earth, and they are present in most habitats. They are capable of existing in extreme conditions including radioactive waste and acidic hot springs, a trait that is often exploited for industrial use. A gram of soil contains about 39 million bacterial cells, while a millimeter of water has about 1 million cells. The total number of bacteria globally is estimated at 5 x 10^30. A fair number of these bacteria have advantageous purposes in agriculture, research, and medicine production.
Bacteria are central in recycling nutrients including fixation of nitrogen and putrefaction. Bacteria have thousands of other functions both natural and industrial. All bacteria are singularly called microbes. They do not have a nucleus or membrane bound organelles. Their genetic codes exist in a single loop DNA. Even then some bacterium contains extra genetic material known as a plasmid.
Plasmid tends to provide additional genetic material that is advantageous to the bacteria such as resistance to antibiotics. The Bacteria exist in 5 different groups. There is the corkscrew (spirochaetes), spherical (cocci), comma (vibrios), rod (bacilli), and the spiral (spirilla). They can exist in pairs, cells, clusters or chains.
Bacteria are known to cause many diseases among them Tuberculosis, pneumonia, tetanus, syphilis, and Typhoid. Even then their potential could be harnessed in the future to provide a means for power. University of Oxford researchers recently used some bacteria to spin rotors of tiny wind farms. This is an exciting discovery for bio-energy researchers. Their next frontier is seeking ways to harness this power and use it to power items like smartphones. When observed under a microscope, you’ll notice that bacteria produces lots of random movements.
This kind of movement has too much spontaneity and in itself cannot produce energy. But then when a lattice of 64 symmetric micro-rotors was immersed into the fluid filled with bacteria it was noted that the bacterial movement organized in such a way that the rotors eventually spun in opposite directions. This flipside turns generated a steady stream of power.
Scientists admit that we won’t be able to power homes with bacteria anytime soon. Even then it will be possible to power micromachines effectively in a short while. The researchers were clear that this power innovation could be extended to self-powered and self-assembled devices.
When one rotor was put in the fluid, it just got kicked randomly. But then when multiple rotors were added they adopted a regular pattern with adjacent rotors spinning in opposite directions. Nature’s ability to stimulate advantageous designs and potential is incredible, and it’s then up to the engineers to figure out how this phenomenon comes about and find ways of scaling it up for future profitable use.
Scientists have continued to make newer discoveries of bacteria from different environmental samples. Since 1980 the number of sightings of bacterial groups has risen from about 12 to about 100, and more than 35 other groups were discovered in 2015 alone. The biggest discoveries were made in Japan, Chile, and California. When commercially explored this discovery could be put to use in powering optical switches, smartwatches, Bluetooth devices as well as smartphones.
This innovation comes in handy especially since scientists are grappling with the impact of fossil fuels and other non-renewable energies. The move toward more eco-friendly power sources from bacteria, signals a bigger step in the development of bio-energy. The most significant breakthrough in the experiment is that the simple structural organization reminiscent of a wind farm was achieved without the use of pre-design microscopic gear-shaped turbines.
The most interesting dynamic is that these biological systems produce the mechanical work without the need for a power input. This dependency on internal biomechanical processes means the processes adopts a level of efficiency that cannot be replicated by lots of other power-production mechanisms
The new challenge for researchers is to establish the process behind this reorganizing principle of biological assemblies in such a way that it can be harnessed to generate steady mechanical power by rotating the rotors. The even bigger frontier for research is to determine whether the newly discovered forms of bacteria can produce an even more efficient reorganization to generate greater power.
Researchers in Japan have taken upon this innovation and added a few features to it. They included an inorganic catalyst to the system to stimulate the movement of the bacteria. The cog-shaped silicon rotor with a circular channel of 2mm and 6mm radius lay flat over its circular track.
Its vertical protrusions dropped into the track to allow it to move freely. The researchers depended on the bacteria Motile Mycoplasma to produce the organized bioassemblies. The channel had deliberately designed topological features to create a unidirectional movement. The bacteria were able to produce about two revolutions power minute as they moved around.
There is no doubt that bacteria produces an incredibly smooth flow of rotors in the channel. There are a few complications to be overcome with such a system, though. Key among them is the need to avoid the presence of isolated proteins that can distract the bioassembly and movement.
The use of bacteria for the conversion of chemical energy to electro-mechanical energy opens doors for creative ways of blending bioenergy and nanotechnology with electronics. This development is a radical departure from the commonly known mean of using bacteria to create biochemical fuel cells.
The bigger challenge besides complexities of scaling up is that bacteria-driven micromotors can lose energy due to internal friction of the moving parts. The reorganization of bacteria still offers exciting applications by aiding active transport mechanisms such as ratchets, valves, pumps, etc.
These two methodologies of harnessing power from bio-movement of bacteria presents two of the most cutting edge innovations in bio-energy development. Even then the discovery of the force behind the bioassembly, the unidimensional movement and the use of catalysts to stir reaction still lingers on.