Superbugs- Conquering the World with Antibiotic Resistance
The History of Superbugs
The fight of humans vs infectious diseases is as old as humanity itself. It was until the discovery of penicillin by Alexander Fleming in 1928 that the homo sapiens finally gained a massive advantage in this war. His discovery was the start of the antibiotic era and thanks to them, bacterial infections were no longer the worldwide death cause number one. In fact, antibiotics were so effective that we were able to prolong the average human lifetime by 10 years! It is all good then, isn’t it? Well no, it isn’t because microbes did find an answer. Nature in fact always finds an answer. This time it is called superbugs. We are on our way to losing the advantage we got because of the antibiotics.
The Bacterial Nature
We need to understand the bacterial behavior to understand how bacteria become resistant to antimicrobials. Microbes (including bacteria) are everywhere. In fact, they are probably the most successful when it is about settling down in places that seem unpleasant to us. However, apart from populating the whole world (including us), bacteria are special because of their love for dividing and replicating.
As soon as they found a place where they feel at home, they multiply rapidly. However, we can not only reduce them on that ability as they possess one even more impressive characteristic: they can share genes — an essential ability for the rise of superbugs.
Anyway, we won’t spoil anything yet. So let’s start talking about genes for a moment. Genes pretty much define who we are. They are responsible for our eye color, body size, hair color (coloring your hair doesn’t count as “modifying your genes”!). All these things are (to a large extend) defined by the genes we got from our mum & dad, and grandma & grandpa, and… you get it.
The same more or less applies to our microscopic friends as they pretty much get the whole genetic dataset of their direct ancestor. Like that, bacteria evolved over time to conquer the world and live at the most freaky places you can think of.
And the same way they can have genes within their cell that makes them resistant to one or several antibiotics. However, we still didn’t talk about the most impressive feature bacteria possess. While humans pretty much have a fixed genetic dataset for their entire lifetime and also don’t mutate really often when the genes of mum and dad form a new human, bacteria are much more flexible and can take up new genes throughout their journey in life.
Pretty much, yes!
Superbugs and how they Evolve
Nature came up with several possibilities for bacteria to gain new genes to make sure we won’t have an easy fight against them (really, we don’t know the reason why nature came up with those possibilities).
- They take up new genes from their environment. This can happen when bacterial cells in their direct environment die and set free their cell contents. This actually comes quite close to robbing a grave.
2. They get infected by a virus and got lucky. Yes, bacteria also can get their own kind of the flu (deadly in many cases). However, if a bacterium gets infected by a virus that infected another bacterium before, it can happen, that the virus does inject genetic material from the bacterial cell it infected recently instead of its own viral genes. As a result, the infected bacterium doesn’t need to worry about a virus replicating within its cell but rather now has the possibility to use the genes of the other bacteria.
3. They have “sex”… in their own weird way. Bacteria can make cell contact through a so-called “pili” and transfer genes through that bridge. This is a really common mechanism, that plays a big role in the spread of antibiotic resistance and the development of sueprbugs.
4. They mutate. Mutations are fighting with a bad image in the year 2021 due to the COVID-10 virus. However, their image won’t really improve when we’re talking about antibiotic resistance. Most mutations in bacteria happen during the replication process. However, most of these mutations are counterproductive. Nevertheless, those few that give the bacterium a selective advantage against other organisms will establish over time out of evolutionary reasons. Future bacterial generations will then also receive these mutations (as bacteria are passing on their genetic dataset).
So that are the four easy ways how bacteria can transform into superbugs (and why humans are lucky enough to not share their ability).
Superbugs and how we add to this
We are not yet screwed but we need to understand how every one of us contributes to the spread of antibiotic resistance and the rise of superbugs.
Let’s have a look at a real-life example some of you might have already experienced. You’re feeling sick and seek the help of a doctor who prescribes an antibiotic therapy. And you are lucky — it is working! After a few days already, you’re feeling better. In fact, you are feeling that good, that you decide you don’t need to take your antibiotics anymore. No problem so far. However, let’s have a look at the inside.
First of all, we need to understand that 1. we are teeming with bacteria inside and on us (just in our gut, there are 100 trillion microbes — most of which, it’s worth noting, are beneficial to us) and 2. microorganisms divide whenever the opportunity arises. Particularly eager representatives can double every 20 minutes!
Through our antibiotic therapy, we’ve essentially cleaned house in our gut. While the antibiotic’s target was primarily the troublemaker that slipped in among the beneficial bacteria, the antibacterial agent couldn’t care less about that distinction. But the good thing about the therapy is that we’ve likely eliminated the majority, if not all, of the intruders alongside all the collateral damage. The downside, however, is that the organisms that survived were either very lucky or already possessed resistance to the antibiotic. These could be completely harmless or even beneficial bacteria — they just happen to carry a resistance gene. Some might already see where this is heading. Our gut inhabitants, including their antibiotic resistance, have little competition now for living space and are taking advantage of the moment to multiply massively. So, our gut is now teeming with microorganisms carrying antibiotic resistance genes. When you put two and two together, it quickly becomes clear that the likelihood of this gene being passed on (e.g., to the next unwanted intruder) has significantly increased — especially if you keep in mind the simple pathways for the spread of such genes. Thus, we can relatively easily breed our own superbug — if one desires to do so.
What might initially sound like science fiction is happening daily right before our eyes. An unimaginably large number of microorganisms are constantly interacting with each other and can evolve through relatively simple means. Antibiotic resistances are also affected by this evolution. So, while it will be essential from a scientific perspective to discover new agents (such as Irresistin) to keep potential infectious disease pathogens in check, we can and must all contribute to ensuring that existing antibiotics retain their effectiveness for as long as possible and that superbugs do not emerge at all.
