In citrate-utilising prokaryotes, citrate lyase EC:4.1.3.6 cleaves intracellular citrate into acetate and oxaloacetate, and is organised as a functional complex consisting of alpha, beta, and gamma subunits. The gamma subunit serves as an acyl carrier protein (ACP), and has a 2'-(5''-phosphoribosyl)-3'-dephospho-CoA prosthetic group. The citrate lyase is active only if this prosthetic group is acetylated; this acetylation is catalysed by an acetate:SH-citrate lyase ligase. The alpha subunit substitutes citryl for the acetyl group to form citryl-S-ACP. The beta subunit completes the reaction by cleaving the citryl to yield oxaloacetate and (regenerated) acetyl-S-ACP. This family represents the alpha subunit EC:2.8.3.10.

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