In enzymology, an indoleacetate—lysine synthetase (EC 6.3.2.20) is an enzyme that catalyzes the chemical reaction

ATP + (indol-3-yl)acetate + L-lysine ADP + phosphate + N₆-[(indol-3-yl)acetyl]-L-lysine

The 3 substrates of this enzyme are ATP, (indol-3-yl)acetate, and L-lysine, whereas its 3 products are ADP, phosphate, and [[N6-[(indol-3-yl)acetyl]-L-lysine]].

This enzyme belongs to the family of ligases, specifically those forming carbon-nitrogen bonds as acid-D-amino-acid ligases (peptide synthases). The systematic name of this enzyme class is (indol-3-yl)acetate:L-lysine ligase (ADP-forming). This enzyme is also called indoleacetate:L-lysine ligase (ADP-forming).

• Glass NL, Kosuge T (1986). "Cloning of the gene for indoleacetic acid-lysine synthetase from Pseudomonas syringae subsp. savastanoi". J. Bacteriol. 166 (2): 598–603. PMC 214646. PMID 3084452.
• Hutzinger O, Kosuge T (1968). "Microbial synthesis and degradation of indole-3-acetic acid. 3. The isolation and characterization of indole-3-acetyl-epsilon-L-lysine". Biochemistry. 7 (2): 601–5. doi:10.1021/bi00842a013. PMID 5644130.