Penicillin antibiotics

A few weeks ago I came down with the flu

This was the third time in 5 weeks I’d got the flu and I was starting to get frustrated. Then, to make matters worse, after the flu left the cough stayed on. This was an annoying cough too, it meant that whenever I was even just walking I’d have a coughing fit and have trouble breathing.

Unfortunately it took me way too long to do the maths and figure out that not being able to breathe a week after the flu had gone was a good reason to visit the doctor.

Of course when I got there, it took the doctor about three seconds to listen to my lungs and tell me that I actually had a chest infection (explains a lot hey). He prescribed me 750mg of amoxicillin to take three times a day and sent me on my way.

Amoxi- what??

When I went into the pharmacy (or the Apotheke here in Germany) I had no idea what amoxicillin really was, but I had heard the -cillin part somewhere before, that’s like penicillin and stuff right?

Of course because I’m a chemistry major and I love chemistry with all my heart, that was enough to get me interested in the chemistry of this thing. If I was going to take this stuff for a week I at least wanted to know what it was.

So what is it?

Amoxicillin is a derivative of penicillin. In maths, that would mean doing a bit of calculus but in Chemistry, that means that it amoxicillin shares the same common structure as penicillin, just with a few carefully placed functional groups added.

Why? Because adding these few extra functional groups gives the molecule different properties and in the case of amoxicillin, this property is that it can fight a broader range of bacterial infections among other things.

How does it work?

Penicillins have a very interesting and unique structure. It contains a β-lactam ring which is unique because it’s a four membered ring which is pretty rare in nature because of it’s instability.

If you’re confused, the ‘corners’ in this diagram for example in the rings represent carbon atoms. The squiggly line shows where the variable part is (those other functional groups I was talking about).

This four ring is rare because the angles between the atoms need to be ~90 degrees, which is very small compared to the preferred 120 degrees of the C=O bond. Basically, the atoms in that four ring would rather be in just about any other conformation except in a ring.

That ring however is where penicillin does it’s magic. This ring is able to open in the body and react with an enzyme that is essential in building bacterial cell walls. Without this enzyme, the bacteria can no longer build or maintain their cell walls and they die.

Why doesn’t this also kill us humans? Because our cells don’t have cell walls like bacteria do, only cell membranes that don’t use that enzyme.

What's the difference between amoxicillin and penicillin?

The original penicillin that was first extracted from the penicillum notatum mold was penicillin G. Amoxicillin is similar to penicillin G, it just has two ‘extra’ functional groups.

Why do we care?

Antibiotics like penicillin are pretty much our only defense against bacterial infection and without them, let’s just say we probably wouldn’t have an overpopulation problem. On the other hand, overuse of antibiotics is causing problems that are arguably just as big. The more antibiotics are used, the more chance bacteria have to mutate and develop resistance to these antibiotics and boy do we overuse them.

It’s not just humans taking too many of them them either, they’re often given to livestock to keep them healthy which then is eaten by humans. Antibiotic resistant bacteria are responsible for 2.8 million infections and 35,000 deaths per year in just the US alone.

My week on amoxicillin was not fun.

Apparently I should have mentioned to the doctor that this was my first time on antibiotics since about when I was born, or maybe I’m just weak. The first time I took the medicine, I lay down to take a quick 10 minute nap before my 3.45pm German class… and woke up 6 hours later.

For this entire post I've been wrongly spelling penicillin as penEcillin

I keep writing penecillin, which got me thinking, what would pennecillin look like…? So I did a little bit of work and here’s the finished product.

I think this might actually be my most groundbreaking work yet, should publish it to a scientific journal?

Of course neither penecillin or pennecillin actually exist 😂😂 but hey.

Update on the quantum posts

Part 2 is ⚠ work in progress ⚠. It’s taking so long because quantum physics is hard and I’m a chemistry major. I’m reading a book about it now though so I can actually understand it more.