Reacylation

Reacylation refers to the addition of an acyl group (R-CO-) to a molecule from which an acyl group has been removed, or more generally to the introduction of an acyl moiety into a substrate that accepts it. It is a key step in acyl-transfer processes across chemistry and biochemistry.

In biochemistry, reacylation is most prominently described in membrane lipid remodeling, known as the Lands cycle. Phospholipids are deacylated by phospholipases A1 or A2 to yield lysophospholipids and free fatty acids. Reacylation then transfers a fatty acyl group from acyl-CoA to the lysophospholipid, regenerating a phospholipid and altering its fatty acid composition. Enzymes called lysophospholipid acyltransferases (LPLATs) mediate this step, and substrate specificity can vary by tissue and organism. This process allows cells to adapt membrane properties in response to dietary, thermal, and metabolic conditions.

In chemical synthesis, reacylation describes reintroducing an acyl group onto a molecule that previously carried one, typically using activated acyl donors such as acyl chlorides, anhydrides, or activated esters, or via acyl-CoA–mimetic approaches in enzymatic contexts. Reacylation is widely used in peptide and lipid synthesis, as well as in protection–deprotection strategies where a temporarily removed acyl group is restored.

Overall, reacylation is a fundamental concept in lipid metabolism and acyl-transfer chemistry, enabling membrane remodeling and the construction of a broad class of acylated compounds.