Four different enzymes share a similar catalytic mechanism which involves the
phosphorylation by ATP (or GTP) of a specific histidine residue in the active
site. These enzymes are:
ATP citrate-lyase (EC 126.96.36.199) , the primary enzyme responsible for the
synthesis of cytosolic acetyl-CoA in many tissues, catalyzes the formation
of acetyl-CoA and oxaloacetate from citrate and CoA with the concomitant
hydrolysis of ATP to ADP and phosphate. ATP-citrate lyase is a tetramer of
Succinyl-CoA ligase (GDP-forming) (EC 188.8.131.52)  is a mitochondrial
enzyme that catalyzes the substrate level phosphorylation step of the
tricarboxylic acid cycle: the formation of succinyl-CoA from succinate with
a concomitant hydrolysis of GTP to GDP and phosphate. This enzyme is a
dimer composed of an α and a β subunits.
Succinyl-CoA ligase (ADP-forming) (EC 184.108.40.206)  is a bacterial enzyme
that during aerobic metabolism functions in the citric acid cycle, coupling
the hydrolysis of succinyl-CoA to the synthesis of ATP. It can also
function in the other direction for anabolic purposes. This enzyme is a
tetramer composed of two α and two β subunits.
Malate-CoA ligase (EC 220.127.116.11) (malyl-CoA synthetase) , is a bacterial
enzyme that forms malyl-CoA from malate and CoA with the concomitant
hydrolysis of ATP to ADP and phosphate. Malate-CoA ligase is composed of
two different subunits.
We developed three signature patterns for these enzymes, the first corresponds
to a glycine-rich conserved region, located in the second half of ATP citrate
lyase and in the α subunits of succinyl-CoA ligases and malate-CoA ligase.
The second pattern, which is located some 50 residues to the C-terminal of the
first one, includes the active site phosphorylated histidine residue. The last
pattern corresponds to a conserved region located in the first half of ATP
citrate lyase and in the β subunits of succinyl-CoA ligases and malate-CoA
April 2006 / Pattern revised.
PROSITE methods (with tools and information) covered by this documentation:
Elshourbagy N.A., Near J.C., Kmetz P.J., Wells T.N., Groot P.H., Saxty B.A., Hughes S.A., Franklin M., Gloger I.S.
Cloning and expression of a human ATP-citrate lyase cDNA.
PROSITE is copyright. It is produced by the SIB Swiss Institute
Bioinformatics. There are no restrictions on its use by non-profit
institutions as long as its content is in no way modified. Usage by and
for commercial entities requires a license agreement. For information
about the licensing scheme send an email to
or see: prosite_license.html.