The Nobel Prize in Chemistry 2002

 

The Nobel Prize in Chemistry 2002
       
  NMR:
To understand, we need to see
 

With NMR the three-dimensional structure of different substances can be studied. Unlike the alternative method, X-ray crystallography, NMR can be applied to molecules in solution. This is a great advantage since the natural environment of the protein is the living cell.

In NMR the sample is placed in a strong magnetic field. Pulses of radio waves are beamed into the sample, the atoms of which “answer” by emitting new radio waves. The result is a spectrum in which each atomic nucleus causes one or more peaks. This is because the magnetic field around each atom is affected by its neighbouring atoms. A large protein gives rise to a very complicated spectrum with numerous peaks.

The different nuclei are identified one after the other in a two-dimensional NMR spectrum, here in a composite diagram in which one can navigate between ‘cross-peaks’ that signal atom proximity.

       
  Many peaks in the spectrum – no problem!    
 

Kurt Wüthrich had an idea for how to find out which peaks correspond to which atoms. His method is called sequential assignment. It involves starting with a signal from a known atomic nucleus and then finding the nucleus in the peptide chain that is signalling that it is a neighbour of the first. Wüthrich matched each signal successively with its atom. With a similar method, which senses the distance between nuclei, he then determined a large number of pairwise distances in the protein, which gave the three-dimensional structure of that protein.

 

If one knows all the measurements of a house one can draw a three-dimensional picture of that house. In the same way, by measuring a vast number of short distances in a protein, it is possible to create a three-dimensional picture of that protein.
     
   

Kurt Wüthrich preparing a protein solution in an NMR tube. His measurement gives a three-dimensional picture of the protein structure in solution. Wüthrich works at ETH in Zürich, Switzerland and at the Scripps Research Institute, La Jolla, USA.
  Contents:
| Introduction | Mass Spectrometry | NMR | From early diagnosis to new medicines | Further reading | Credits |
  Web Adapted Version of the Nobel Poster from the Royal Swedish Academy of Sciences

To cite this section
MLA style: The Nobel Prize in Chemistry 2002. NobelPrize.org. Nobel Prize Outreach AB 2024. Thu. 26 Dec 2024. <https://www.nobelprize.org/prizes/chemistry/2002/8861-the-nobel-prize-in-chemistry-2002-2002/>

Back to top Back To Top Takes users back to the top of the page

Nobel Prizes and laureates

Nobel Prizes 2024

Six prizes were awarded for achievements that have conferred the greatest benefit to humankind. The 12 laureates' work and discoveries range from proteins' structures and machine learning to fighting for a world free of nuclear weapons.

See them all presented here.

Illustration

Explore prizes and laureates

Look for popular awards and laureates in different fields, and discover the history of the Nobel Prize.