[3] In plants, ATP citrate lyase generates cytosolic acetyl-CoA precursors of thousands of specialized metabolites, including waxes, sterols, and polyketides.
[4] De novo fatty acid biosynthesis in plants occurs in plastids; thus, ATP citrate lyase is not relevant to this pathway.
[8][9] The enzyme is composed of two subunits in green plants (including Chlorophyceae, Marchantimorpha, Bryopsida, Pinaceae, monocotyledons, and eudicots), species of fungi, glaucophytes, Chlamydomonas, and prokaryotes.
[3] In 2019, a full length structure of human ACLY in complex with the substrates coenzyme A, citrate and Mg.ADP was determined by X-ray crystallography to a resolution of 3.2 Å.
[10] Additional structures of heteromeric ACLY-A/B from the green sulfur bacteria Chlorobium limicola and the archaeon Methanosaeta concilii show that the architecture of ACLY is evolutionarily conserved.
The C-terminal region of ACLY assembles in a tetrameric module that is structurally similar to citryl-CoA lyase (CCL) found in deep branching bacteria.