Adenylylation

Adenylylation, now known as AMPylation, is a process in which adenosine monophosphate (AMP) molecule is covalently attached to a protein side chain, altering the function of the protein. This covalent addition of AMP to a hydroxyl side chain of the protein is posttranslational modification that is stable and reversible. Adenylylation involves a phosphodiester bond between a hydroxyl group of the molecule undergoing adenylylation and the phosphate group of the adenosine monophosphate nucleotide (i.e. adenylic acid). This process can occur to molecules such as tyrosine residues. Enzymes that are capable of catalyzing this process are called AMPylators.