Natural choice when making proteins?

Yale University chemists did what nature chose not to do - to create protein-like molecules from unnatural blocks, according to an article published online recently in American Chemical magazine. Society.

Nature uses the alpha-amino acid fusion block to form this protein and protein to make life as we know it. Yale University chemists have now published evidence that nature may have used another fused mass - beta-amino acid - to make proteins and they also proved that, the Peptides made from beta-amino acids can be folded into structures very similar to natural proteins

'The X-ray structure described in the article shows that a beta-peptide molecule shares many structural properties of natural proteins ,' said the lead author of the paper, Alanna Schepartz, professor of chemistry at Yale University. and Howard Hughes Medical Institute, said. 'Related studies have also demonstrated that the physical properties of this molecule are remarkably similar to natural proteins. In other words, the beta-peptide block looks very similar and works very much like a true protein. '

Bundle beta : Ribbon chart of a bata-peptide bundle illustrating ' packaging ' between spiral lines and between hydrophobic core (blue) - (Photo: Schepartz / Yale)

The ability to mimic natural proteins makes beta-peptides into powerful and useful new tools in basic research and discovery. Like a videotape, the greatest value of beta-peptide may lie in their differences compared to a live performance.

'Because the non-cellular beta-peptides are like natural peptides or proteins, in the future we will be able to produce beta-peptides that are better or more active than current protein drugs. , ' Mrs. Schepartz said. 'Beta-peptides may also have unique properties of biofuels.'

Natural proteins include sequences of straight alpha-amino acids. Beta-peptides include beta-amino acids, which have an additional carbon in their backbone. Like alpha-amino acids, beta-amino acids formed in pre-biotic conditions are activated and are a by-product of metabolic processes, but they do not encode genetic information like natural proteins. , nor can the cells form the chain .

Since the early 90s, scientists have been able to ' assemble ' the beta-peptides into separate helices. However, until now, the creation of a structure that mimics the large size and complex folding structure of a natural protein is still a difficult goal.

However, Ms. Schepartz's research team solved this problem, by designing a molecule capable of forming a bundle that bears the characteristics found in natural proteins - the inner part of greasy water and water-friendly exterior. This article provides the first high-resolution photograph of a structure like that, showing a bundle of 8 beta-peptides.

Schepartz said: 'The structure we see is very attractive, because it shows that natural proteins may have included beta-amino acids but they are not chosen to do so.'

Thanh Van