When there are no external nucleophiles added, other amino acids can react with the episulfonium intermediate in an intramolecular reaction. That reactivity allows for protein-protein ligation and ...

In a new peer reviewed analysis, scientists quantify amino acids before and after our “last universal common ancestor.” The last universal common ancestor is the single life form that branched ...

Nu, nucleophilic amino- acid residue ... between the reaction site of the labeling agent and the reactive amino acids on the target protein. In this approach, it is difficult to target proteins ...

"The challenge arises from the fact that all proteins are made from 20 amino acids in various combinations," he said. "Identifying a modifiable functionality at the desired site, not repeated ...