What is antibiotics? Chemistry Calendar, October: Health

Uploaded by MoleCluesTV on 08.11.2011


Well, there are many ingredients to a healthy life.
For example eating right, doing physical activity and trying to stress less.
But there are times when we need that little extra help from medicines.
Not long ago, this happened to me.
And soon after, this.
I was given antibiotics, and ten days later all my symptoms were gone.
The question is how?
Let’s go and learn some more about antibiotics!

Can you take a look at this and see what it looks like?
All gone?
All gone. You’re healthy.
Perfect, thank you.
Well, the reason I got antibiotics in the first place
was because I had the symptoms of Lyme disease,
which is caused by a bacteria that is transferred by ticks
and it can cause pretty big problems if it’s left untreated.
The antibiotics stopped my bacterial infection,
but the other cells in my body were obviously not affected.
How does this work?

So the word antibiotics literally means 'against life'.
But we are of course not interested in wiping out all life,
only certain infections.
So the trick is to find a way to kill only those bad bacteria.

To learn some more I meet up with Kristina Hedfalk.
My name is Kristina Hedfalk
and I am a researcher in biochemistry at the University of Gothenburg.
Antibiotics can have different actions on a bacterial cell.
One thing is that the cell wall, present in the bacterial cell is not present here,
so that is something that can be targeted.
And also, the mechanism of protein synthesis
is also one very common action mechanism for antibiotics.
So let's revise this first.
Animal cells and bacterial cells have many differences,
besides that fact that bacteria are much smaller.
Some of these differences can then be targeted
so the antibiotic only harm the bacteria.
For example, both bacterial cells and animal cells have DNA,
although in animal cells it is enclosed in what is called a nucleus.
But the DNA do the same job in both, it codes for the production of proteins,
called protein synthesis.
No matter if it’s a bacterial cell, or if it’s a mammalian cell or a plant cell,
there is a lot of activities going on here to keep the cells alive and the organism alive.
And for this to happen you need proteins,
because proteins are the units that do, or perform, all the functions in the cell.
Okay, so pretty important, right?
And if we were to interrupt a step in this process
we would pretty much stop the whole cell to function.
So if we wanted to design an antibiotic that targets the protein synthesis
we would first need to fully understand this process.
Protein synthesis starts with the DNA being transcribed to RNA.
The RNA is then read, or translated, by ribosomes,
which are actually proteins themselves.
The ribosomes then add amino acids together in the order the RNA is coded,
to form a specific protein.
Some antibiotics we use today, like the one Jonas got for his Lyme disease,
target the function of the bacterial ribosomes, and the bacteria dies.
But luckily, these anitibiotics do not accumulate in the human cell and harm us!
Okay, so all this sound pretty straightforward, right?
As soon as we get a bacterial infection we’ll just take antibiotics, right?
Unfortunately, a big problem right now is bacteria developing a resistance
towards the available antibiotics.
So antibiotic resistance, that means that there are bacteria that can survive
even if the antibiotic is present.
So that means that the antibiotic is not effective.
Okay, let’s try to explain this.
If an infection was only one or a few bacteria, it would be pretty easy to get rid of.
But instead it involves millions of bacteria and they multiply extremely fast
and not always exactly the same.
When we have a large population size like this, there is a bigger chance, or risk in this case,
that one will develop a certain characteristic
that could result in resistance towards the antibiotic.
So this is becoming a big problem now and a lot of research is going on
to find new and improved ways to fight bacterial infections.
And now we know that the key to an effective antibiotic lies in the research
behind finding a proper target that affects only the bad bacteria.
But so far we have to think about only using antibiotics when we really have to.
Plus, remember that there is a lot of good bacteria in our bodies too
that we don’t want to disturb unless it’s really necessary.

So we know that a healthy life involves several things,
but sometimes we do need to take medicines.
And if it wasn’t for chemical research,
we wouldn’t have many of the medicines we have today.
But it’s not over.
Everyday lives are lost because of health related issues and diseases.
So the important research continues,
and this might be something you can help with in the future!
So remember, Chemistry is all around You!