Molecule of the Month: Monellin
Monellin and other supersweet proteins trick our taste receptors.
Exploring the Structure
Since it’s so sweet, monellin would be great for creating diet foods, since only a little is needed. However, it rapidly loses its sweetness when heated, so it’s not much good for baking. To solve this problem, researchers have engineered new heat-stable forms of monellin by connecting its two chains. To explore natural monellin (PDB entry 3mon) and two engineered single-chain forms (PDB entries 1mol and 1fa3), click on the image for an interactive JSmol.
Topics for Further Discussion
- Thaumatin is often used as a test system when researchers are developing new methods for protein crystallography, since it is readily available and easily forms crystals. Try searching for “thaumatin” to see some of the ways it has been used.
- The proteins lysozyme and mabinlin also taste sweet, although not as sweet as the proteins shown here—try searching for them to explore their structures.
July 2016, David Goodselldoi:10.2210/rcsb_pdb/mom_2016_7