May the Force be with you
May the Force be with you
How our bacteria give us superpowers.
May the Force be with you! Who doesn't know the legendary farewell greeting of the Jedi from the Star Wars universe? The Force gives them special powers: they can levitate things, influence people, dodge enemy laser swords at lightning speed and whirl effortlessly through the air in battle. Unforgettable, however, is the scene in the 5th part of the saga, when the Jedi Master Yoda makes Luke Skywalker's spaceship emerge from the swamp with the power of the Force alone.
In parts 4-6, which were filmed chronologically first, the Force is still something abstract, which the Jedi Knights may only use for defense and protection. They must not abuse it, otherwise they will end up on the "Dark Side of the Force".
But in the following episodes 1-3 this is explained in more detail. It is about the smallest microorganisms, the so-called midi-chlorians, which work symbiotically in the cells of all living beings. However, only when the concentration in the blood is high enough the power can be controlled. Without the midi-chlorians no living being could exist. They communicate continuously with their carrier.
What a great science fiction story. But is it really that unbelievable?
The importance of the microbiome is underestimated
Nowadays, the microbiome is still vastly underestimated by the general public, and in some cases not even acknowledged. This is not surprising, since scientific research on the human microbiome is still rather young.
But what is the microbiome? There are a lot of living organisms on and in the human body. Bacteria, archaea and fungi and the genetic pool they represent form the microbiome. If the definition is explicitly limited to living organisms without including the expansion of the genetic pool, the term microbiota is used.
the microbiome is much more than just a new market segment for the pharmaceutical industry
Scientists have been studying the microbiome for the past 20 years. In industry, on the other hand, a trend has been evident for a little more than 10 years. Large pharmaceutical companies are still waiting until the smaller, R&D-focused life science companies will bring convincing products to market.
But the microbiome is much more than just a new market segment for the pharmaceutical industry. It has accompanied humans since the dawn of Homo Sapiens 200,000 years ago. Its influence on the entire human organism is enormous. And yet - for the non-specialists, it is still just a few bacteria that live with us - an accepted fact of life.
They are many
We are not just talking about a "few" bacteria. A human being consists of approximately 10-30 trillion human cells. On and in the body there are 100 trillion bacterial cells. In addition, there are 10,000 trillion viruses. The ratio of bacteria to human cells is therefore a maximum of 10:1. If you were to line up all the bacteria, then with an average size of a bacterial cell of 2 µm, you would arrive at a total length of 200,000 km. That is half the distance to the moon or five times the perimeter of the earth. In a single human being!
For decades, the role of bacteria had been seen only in the utilization of food in the intestine. When I talk to non-specialists and ask them if they can tell me the name of a bacterium, I might hear Salmonella or Legionella. Very rarely also Listeria. These are all bacteria that are pathogens. Then when I start to rave about the bacteria, that we could not survive without them, I am usually confronted with an uncomprehending shrug of the shoulders and an almost pitying look of "Typical scientist". In these moments, I ask myself how the person I'm talking to would react if I were to perform a change of perspective at the next opportunity.
Talk partner: Hey, I had violent heart palpitations last night. That gave me quite a scare.
Me: Why? It's just a heart, isn't it?
Talk Partner: What do you mean? The heart is THE center of our body. Without the heart we could not survive?
Me: Oh, don't make such a fool of yourself. It's just a muscle. And we have many muscles.
An incredible number of genes
Of course, the job of the bacteria is much more significant than just being our food digesters and exiting through our anus. If we were to think of bacteria as blue flares, we would glow blue through and through. There are hardly any places in our bodies that are not invaded by bacteria. And they are not only annoying fellow inhabitants, but they are vital partners in all areas of our body! In principle, there is not even one microbiome. In fact, there are many small microbiome satellites in our body. The bacterial communities of our intestines are different from the bacteria in our mouths, which again are different from the bacteria on our skin. For a long time, for example, it was thought that the lungs were bacteria-free. In fact, however, there are bacterial populations there as well, just as there are in the blood, which is also not sterile.
The ego of the entire human race was scratched all at once.
Humans have about 23,000 genes that code for proteins, which are used as structural substances or enzymes. Nematodes have the same number of genes. At their discovery, the small number of genes had caused a storm of indignation. This cannot be allowed to happen! Surely we cannot compare ourselves with a worm? The ego of the entire human race was scratched all at once. It must have been the same when Copernicus described in his heliocentric world view that the earth rotates around the sun and not vice versa. Humans do not like it, if they are not represented as the climax of the creation.
But the gene pool increases abruptly if the genes of the bacteria are counted. There are different estimates for this. Experts believe that every human being possesses more than 10 million different bacterial genes, which extend its abilities dramatically. However, there are also studies which assume that all the bacteria in our body possess 100 million genes and more!
Our superpowers
Genes can be roughly divided into producing and regulatory genes. Regulatory genes control all genetic activity. Producing genes are responsible for the production of protein molecules, which are used either as building materials or as enzymes. Enzymes, in turn, allow new substances to be formed in the body.
The bacteria in our body have therefore given us the opportunity to form many substances that our human cells would not be capable of producing. These substances fulfill vital functions and give us unexpected new abilities. This could be observed very well in mice: Germ-free mice, i.e. animals specially bred in the laboratory without bacteria, contain only 52 chemical substances in their blood, while "normal" mice, i.e. animals that have come into contact with bacteria, contain 4,200 substances.
Bacteria allow us to survive
If we did not have our bacteria, we would not have the slightest chance of surviving in our environment. And that is exactly the reason why we entered into this symbiosis 200,000 years ago. Bacteria allow us to survive and we provide the bacteria with nutrients.
True companions for a lifetime
Our bacteria are with us throughout our lives. In the microbiome satellites of our body they form communities, which produce exactly at this place at the right time, the right substance, which interact with our metabolism. In addition, their numerical presence suppresses the growth of pathogenic bacteria.
This fact was not known until recently. Therefore, the question arises, why should we care about it now? Quite simply. The caveman did not have the tools we have today. We are continually changing the bacterial populations that live with us through antibiotics, cesarean births, toxins and sterile environments. And this in a negative sense.
This is especially striking with the Corona-induced sterility hysteria. Disinfectants are sprayed everywhere, we are told to wash our hands constantly, and there are reminders lurking everywhere that we should keep ourselves as sterile as possible. The fact that the microbiome is massively damaged in this way can come as no surprise. As a result, we continuously reduce the diversity of our microorganisms and become increasingly vulnerable to diseases.
Worldwide increase in diseases
In biology, it is well known that symbioses only work when both sides benefit. For thousands of years, this was the case. But today, this is no longer true. While we focus on the extinction of animal species, an equally dramatic process is taking place within us. The extinction of our good bacteria and the takeover of the resulting niches by pathogenic and often antibiotic-resistant bacteria is a gradual process. Globally, nearly 5 million people died in 2019 related to antibiotic resistance. But how many people are already dying because their microbiome is no longer efficient enough? How many people become seriously ill because their microbiome no longer protects them?
We need the bacteria to survive. On the other hand, the bacteria do not need us.
This number is difficult to measure based on the current state of research but, in my opinion, may already exceed the number of deaths associated with antibiotic resistance. We are currently only at the beginning of the overwhelming realization that many so-called diseases of civilization are caused by an altered microbiome. But cancer, diabetes I in children, obesity and other microbiome-associated diseases already speak for themselves. The reason why this worrying development is not discussed more often is simple: Firstly, it is difficult to quantify and secondly, there are still no expensive drugs that specifically influence the microbiome in a positive way. It may seem trivial but unfortunately our market economy ticks like this: no profit, no money, no media spotlight.
The bacteria do not care about our lack of attention. Because we must not forget: We need the bacteria to survive. On the other hand, the bacteria do not need us.
Only we are responsible for our health
But the struggle of the few experts and scientists against the dying of our microbiome will not be enough if the true importance of bacteria remains largely unknown to the majority of the population. The spotlight of attention - profit or no profit - must not only be directed at the worldwide increase in antibiotic resistance. No support can be expected from politics in this regard. The current corona crisis shows how incomprehensibly low the competence of politicians in the health sector is, how poorly they actually care about health, and how low their willingness is to think outside the box.
Why should the government be interested in a comprehensive educational campaign?
Therefore, everyone must make the decision for themselves whether they want to inform themselves and do something on their own against the breakdown of their microbiome. We must finally stop believing that the government or "anyone else" will take care of our health. Personal responsibility and self-determination are needed.
Decreasing diversity of our microbiome will lead to further stress on the health care system in the near future. But we must not forget that the essential driver of economic growth is the healthcare business. And that works poorly with healthy people. So why should the government be interested in a comprehensive educational campaign?
Who are WE?
We must ultimately change our beliefs to come to a more natural way of dealing with our bacteria. The old worldview in which humans, superior to everything else, must live more or less with bacteria is outdated.
Instead, we should consider the idea that we are a multi-organism being made up of large cells (the eukaryotic cells) that mix with bacterial cells, archaeal cells, fungi, and viruses to form a life form. Only that mixture of cells can survive. And this mixture are WE!
Once we have understood this, we will take care of it in our everyday life. As we will pay attention that we do not lose a leg or another body part carelessly, so we will pay attention that we do not kill our own bacteria.
But to do that, we must first accept and believe in the superpowers of our bacteria.
And that brings us back to the introductory scene from Star Wars mentioned above. Luke could not believe that his master Yoda lifted the spaceship, which weighed tons, out of the swamp with the help of the Force, in other words, by means of his microorganisms.
Luke: I don't, I don't believe it.
To which Yoda replies:
That is why you fail.
Further literature and references
Global burden of bacterial antimicrobial resistance in 2019: a systematic analysis. https://doi.org/10.1016/S0140-6736(21)02724-0
Tierney BT, Yang Z, Luber JM, et al (2019) The Landscape of Genetic Content in the Gut and Oral Human Microbiome. Cell Host Microbe 26:283-295.e8. https://doi.org/10.1016/j.chom.2019.07.008
Star Wars: That is why you fail.
W. R. Wikoff et al., “Metabolomics analysis reveals large effects of gut microflora on mammalian blood metabolites,” Proceedings of the National Academy of Sciences 106 (2009): 3698–703.