N<sup>2</sup>-citryl-N<sup>6</sup>-acetyl-N<sup>6</sup>-hydroxylysine synthase (, N(alpha)-citryl-N(epsilon)-acetyl-N(epsilon)-hydroxylysine synthase, iucA (gene)) is an enzyme with systematic name citrate:N<sup>6</sup>-acetyl-N<sup>6</sup>-hydroxy-L-lysine ligase (ADP-forming). This enzyme catalyses the following chemical reaction
This enzyme requires Mg<sup>2+</sup>.