Photosynthetic microorganisms depend on sunlight to survive. In fact, it is necessary that you produce the energy your body needs. A new article published today in PNAS magazine reveals the secret of these microscopic creatures. This new study, conducted by researchers from the University of Chicago and the University of Washington at St. Louis, suggests that photosynthetic bacteria use quantum mechanics to avoid dying.
“Prior to this study, the scientific community had discovered quantum signatures created in biological systems and asked themselves the following question: Were these fingerprints simply a consequence of the fact that biology was made up of molecules, or did they have a purpose?” Greg said Engel of the University of Chicago and lead author of the study, cited by Science Alert.
Chlorobium tepidum, an amazing bacterium
As part of their work, the scientists analyzed a microorganism called Chlorobium tepidum. It is a phototrophic anaerobic bacterium that is also thermophilic. In other words, Chlorbium tepidum needs light to stay alive. However, their photosynthetic system is extremely vulnerable to oxygen.
What is useful to us in releasing the energy glucose provides in our cells can therefore destroy the mechanism by which light is converted into chemicals in photosynthetic microbes.
A quantum effect for energy transfer
To avoid such a catastrophe, Chlorbium tepidum has developed agents that allow it to reduce the damage that occurs when exposed to oxygen. The means in question are to direct energy to where the body is least at risk.
Chlorbium tepidum has developed agents that allow it to reduce the damage caused by exposure to oxygen. Photo Credit: Shutterstock / MichaelTaylor3d
To investigate this mechanism, the researchers followed the movement of energy through a photosynthetic protein under different conditions, namely with and without oxygen. By doing this, they were able to determine that the bacteria used a quantum mechanical effect called vibronic mixing to transfer energy between two different pathways, depending on the presence or absence of oxygen.
An important discovery
In the absence of oxygen, the microorganism takes advantage of the vibronic interaction by bringing the energy gap between two electronic states together in a mixture of molecules and proteins called the FMO complex (Fenna-Matthews-Olson). This shifts the energy via the “normal” route to the photosynthetic reaction center, which is full of chlorophyll.
And when oxygen is present, the bacteria adapt their bodies to direct energy in a less direct way that it can be attenuated by. According to the researchers, this finding is of great importance in that it proves that certain living things use quantum effects to increase their life expectancy. They also believe that this mechanism doesn’t just affect Chlorbium tepidum.