Helloooo you wonderful bean,

Are you ready to find out just how things glow !?

I knew you were.

Excellent. Let’s get cracking.

So bioluminescence is the result of a chemical reaction. Now this chemical reactionso high in energy that it produces a photon i.e. light.

Now to take you back to the depths of any biology you once studied we’re gonna talk about enzymes.

Enzymes are proteins in your body that act as little catalysts , speeding up all of the chemical reactions that take place in your body.

Just to put in perspective how important these little guys are, there’s a reaction in your body that produces haemoglobin (the lovely molecule we use to transport oxygen around the body) and without enzymes it would take about 2.3 billion years.

Yeah — that’s about half of the age of the Earth. Enzymes = muy importante.

The other fab thing about enzymes is that they are super specific. They can only catalyse one (or maybe at a push two) reactions. This is why they are often talked about in the context of the lock and key model.

The enzymeis the lock and can only be used by a very specific substratemolecule ( key). The substrate locks into a special part of the enzyme and forms the enzyme-substrate complex. The enzyme does its magic and the substrate products yeet themselves out of there.

If that didn’t make any sense — take a look at this handy GIF :

Now in this example the enzyme is called luciferase and the substrate is called luciferin (pretty easy to remember eh?) from the Latin “ lucifer"meaning “ light- bearer".

This works because when these bad boys (enzyme and substrate) come together, the molecule at the end is so high in energy that it can release that photon.

Now this can either be done by the organism itself or it can be done by friendly symbiotic bacteria. In exchange for their light-producing abilities the bacteria get food and a safe place to live — EVERYBODY WINS.

But there is a big question here.

How do you evolve the ability to glow? **

Something had to do it for the first time once. And we think its evolved over 40 different times throughout evolutionary history. That’s a lot. In fact some species (like the lovely anglerfish) have evolved it twice. They have not one but TWO different light emitting systems.

Their lure that sticks out over its head is produced by some lovely symbiotic bacteria and it has a chin barbel that uses some slightly funky chemistry we don’t fully understand.

Fear not. I have the answers or at least what smart people think the answers are

Now — luciferins are actually really good antioxidants. That term might ring a bell. People talk about them a lot, but usually in the context of blueberries and health supplementsinstead of in weird deep sea glowing fish weirdos.

Basically what antioxidants do is they neutralise unstable molecules called free radicals. These molecules are super unstable because they have an unpaired electron that wants to react with anything it bumps into.

You might have heard about these free radicals in the context of UV light. Rays of UV light can produce free radicals inside your body. That’s why it’s so important to wear your sun cream kids — if those free radicals find a nice skin cell to wreak havoc in — that’s skin cancer.

BUT.

If you live really, really deep in the sea the UV light won’t reach you so you don’t really need antioxidants maybe that means that if you live in the dark it’s more useful to use your luciferin to create light instead of using it as an antioxidant.

ISN"T THAT SO COOL?!

Hope you enjoyed. Don’t forget to stay fabulous and party like you’re a comb jelly.

Lots of love,

Flora xxxx