Saturday 8 May 2010

A little bit about little things that do stuff

What is protein? Well, most people think of meat, and maybe milk and cheese, or baked beans. Foods that are rich in protein, that we need to live. In fact the vast majority of people in the western world over consume protein, but we can talk about that another day. Anyways, really we should say, what are proteins? 
The whole of biology is concerned in some way or another with what proteins do. If a living thing is like a car, proteins are the engine, and the hydraulics, and the wheels and the headlights. They are the doers in the situation, the moving parts. I guess the DNA would be the driver, and everything else would be the frame... 
OK so it's hard to make analogies with something as complex as a living thing, but basically proteins are a remarkably diverse collection of molecular machines. And yet the elegant thing is that they are really fairly simple. They're composed of 22 possible basic ingredients (Amino acids), which are put together in chains, which then fold up around themselves. These are then sometimes garnished with a few extra bits, called aesthetic groups. And then they can all play together and with pretty much any other kind of molecule and make stuff happen. Let the whole thing go for a few billion years and abra-cadabra, you have life as we know it. 
OK evolution is a bit more complicated, and yeah DNA is what carries the instructions, but really, the double helix can bugger off out of the limelight. The science guys on TV seem to be very impressed about the whole code-of-life story, but I think that misses the point a bit; it's proteins that are the actual prose of life, DNA is more like the alphabet. I think it's more exciting that we're now figuring out what the words actually mean, rather than the fact that we managed to get what the letters sounded like. How's that for analogy? At least now I'm slightly more excited about the funny things life is made of.
So my first exam is just all about these tiny little buggers, how they do business with their co-conspiritors the nucleic acids (DNA and RNA) and how we study them. It's really important, fundamental stuff, and there's alot of it. So I need to get down to the details today, hardcore. But it's doable... it's the other exams I 'm more worried about.



This odd shape is the structure of my favourite protein of the moment, luciferase. It's what makes the light in a firefly. It's name is just a name for the devil plus -ase, which means a protein that makes a reaction happen. In this case, a pretty cool reaction, which I can talk about more when I go into pyrosequencing; using flashes of light to read a strip of DNA... 
Yeah, this revision thing'll get done, no problem...



Here is the best acronym I have ever found, which I came across during my brief time I actually did, sorta, revise. If you want to know what that unexpected protein was in that sample, you can just check if it's cRAP. Science is for people who like cool names.


P.S. This post counts as yesterday, because I haven't been to bed yet. So I'm not due a facial poke. This counts as revision, doesn't it? No?

No comments:

Post a Comment