The 2015 Nobel Prize in Medicine – Periodic Table of Videos
November 8, 2019
For the first time since we started making these Nobel Prize videos, the Medicine Nobel Prize has got such a strong chemical content that we are going to make two: one about chemistry and this one, which is about medicine. And the reason why we are doing the medicine one is because it is recognizing people who have discovered fundamental molecules that can be used for treating disease. In fact, natural products, compounds nature makes, but people isolated them, they found their biological properties and it brought back a lot of memories for me. The prize was divided among three people, but half to two of them, the other half, to one person: Dr Youyou Tu, in China. And I’m going to talk about the Chinese prize winner, because, as you’ll see, her discovery is pretty close to my heart My colleague, Rob, our organic chemist, is going to talk about the other half of the Nobel Prize. Not so much about the people as about the chemical, because, as you’ll hear, it’s got a special meaning to him. [Rob] Back as an undergraduate, in 1992, my very first project was working on a compound related to Avermectin, which is one of the compounds which was discovered, and which was awarded… the discovery of which was awarded the Nobel Prize this year. [Brady] Avermectim? [Rob] Avermectin, yeah, yeah. So, people may have heard of Ivermectin, which is the… it’s used as a sheep dip. So, literally, you dip the sheep in it, and it gets rid of any parasites on the sheep and it works for, you know, a wide variety of things, human beings, even. But, the reason I was working on it is because it doesn’t work on collie dogs. So, actually there are certain types- breeds of dogs which if you give them Avermectin, they’ll have a heart attack and they die. [Professor] The chemical that Youyou Tu discovered- and, I should say that she is the first Chinese scientist to win the Nobel Prize for work done in China, and, also she is one of the relatively few women that have won Nobel Prizes in science. The molecule she discovered is called artemisinin, which is a very potent treatment for malaria. The reason why it has this rather strange name, ‘artemisinin’, is because it is made as an extract- or, one of the ways of obtaining it is an extract from a plant called ‘Artemisia annua’, which grows in China, and has grown in China for as long as anybody can remember, generations. It has been a traditional treatment for malaria. Now, it’s very important to say that the Nobel Prize Committee said that they were recognising the chemical achievement, not traditional medicine, though, traditional medicine, in this case, was what led to the discovery. [Rob] I was working on this compound here. Here’s Avermectin. So, you can see, It’s quite a complicated structure. It’s got this very unusual macrocyclic lactone here, and the milbermycins are the same compounds, but without this sugar side chain. [Brady] And that’s what you were working on. [Rob] Yeah, that’s what we were working on. So we were taking this fermentation product. So, these all come from streptomyces’ fermentation, and we were breaking it down and building it back up to make a molecule which would retain the anti-parisitic properties, but didn’t kill the collie dogs. [Professor] The real intellectual achievement of Dr Tu was that she realised that the modern traditional treatment, which was extracting the plant and then boiling the extract, seemed to produce something that was not very effective. So, she went back to the ancient texts and discovered that in the old days, people didn’t boil it, and this led her to looking at much lower temperature extracts to see what she could find. You can see the importance of this if you look at the structure of artemisinin which has an oxygen-oxygen single bond, and these bonds are notoriously weak. So, if you boil the solution of the molecule, it’ll decompose. So, people were extracting artemisinin, and then destroying it by boiling. It was a really simple but clever idea that led to the discovery. [Brady] That seems almost too simple for a Nobel Prize. [Professor] Well, very often, Nobel Prizes are based on simple ideas. Graphene was discovered by using sticky tape to remove layers of graphite. So, I think you have to be a real genius to have a really simple idea. [Rob] It’s like a great, big chess game. You’ve got to tweak and change and degrade a molecule and build it back up using the rules of chemistry- the chemical reactions that are available. It takes a real strategy and a real technique to understand how to do that and how to build it up. So, we scanned five or six different roots to make our particular drug molecule- completely different roots, but they all started from the same fermentation precursor, they all ended up with the same drug molecule. [Professor] In this case- and the reason why I feel such a personal empathy is because artemisinin is a molecule that I and my colleague Mike George have been working on for several years. So, you can see our video on greener ways of making artemisinin which we’ve developed here in Nottingham. And, in fact, on the day that the prize was announced, I was giving a lecture in Lisbon in which I was talking about artemisinin. And, after lunch at the conference, the chairman stood up and announced the Nobel prize for artemisinin and everybody burst into applause, and I felt a tiny bit of reflected glory. [Rob] This, actually was the first scientific document I ever wrote. So, this is 1992, I was just a third year undergraduate at the time. And, obviously when you work in a company, this is embargoed- a secret but, because that’s over twenty years ago now, I can disclose this compound here, although these are known in the literature anyway. But, actually it was written in Word 5.1. So, it’s taken me about twenty-five minutes to find something which would open this document. In fact, I’ve lost the front page. [Professor] I think there is a very important lesson in Dr Tu’s Nobel Prize. She is a scientist who has worked all her life in China. She has not gone to prestigious labs in other countries. And, she has published her work, but not in famous journals like Nature and Science, and these other journals. but it demonstrates that really original science can be recognised without looking at some of the parameters that younger scientists now worry about. What is the status of the journal?- and so on. So, if you are a young scientist, it is the quality of your ideas that are important, and if your ideas are really good, they will be recognised. So, don’t broadcast this till we get back. The question that I think you’ll all be wanting to know is how much does it weigh? What is the gold worth? And so, just to answer your question, I brought a balance. And that’s also in my pocket. It’s quite a nice little balance. So, here goes: weighing a Nobel Prize!