MIT and Harvard University chemists have found the structure of a unique bacterial enzyme that can split an amino acid found in collagen, which is probably the most abundant protein in the human body.
The enzyme, referred to as hydroxy-L-proline dehydratase (HypD), has been available in a few hundred species of microorganisms that reside in the human gut, including Clostridioides difficile.
The enzyme acts as a unique chemical reaction that split hydroxy-L-proline, the molecule that provides collagen its sturdy, triple-helix structure.
Now that researchers know the structure of the protein, they cab develop medicines that include this protein. Such a medicine could be useful in treating C. difficile infections that are resistant to many existing antibiotics.
Drennan and Emily Balskus, a Prof. of chemistry and chemical biology at Harvard University are the senior authors of the study, which features today in the journal eLife. MIT graduate pupil Lindsey Backman and former Harvard graduate scholar Yolanda Huang are the chief authors of the study.
The HypD enzyme is an element of a large fleet of proteins named glycyl radical enzymes. These proteins work unusually, by changing a molecule of glycine, the simplest amino acid, into a radical—a molecule that has a single unpaired electron.
Since radicals are very unstable and reactive, they can be utilized as cofactors that are molecules that help push a chemical reaction that might otherwise be troublesome to execute.