|PROSITE documentation PDOC00422
Citrate synthase signature
Citrate synthase (EC 188.8.131.52) (CS) is the tricarboxylic acid cycle enzyme that
catalyzes the synthesis of citrate from oxaloacetate and acetyl-CoA in an
aldol condensation. CS can directly form a carbon-carbon bond in the absence
of metal ion cofactors.
In prokaryotes, citrate synthase is composed of six identical subunits. In
eukaryotes, there are two isozymes of citrate synthase: one is found in the
mitochondrial matrix, the second is cytoplasmic. Both seem to be dimers of
There are a number of regions of sequence similarity between prokaryotic and
eukaryotic citrate synthases. One of the best conserved contains a histidine
which is one of three residues shown  to be involved in the catalytic
mechanism of the vertebrate mitochondrial enzyme. We used this region as a
April 2006 / Pattern revised.
PROSITE method (with tools and information) covered by this documentation:
|CITRATE_SYNTHASE, PS00480; Citrate synthase signature (PATTERN)
H is an active site residue
|Sequences in UniProtKB/Swiss-Prot known to belong to this class detected by PS00480:
||111 true positives with 1 false negative and 2 partials.
|Other sequence(s) in UniProtKB/Swiss-Prot detected by PS00480:
|Matching PDB structures:
1A59 1AJ8 1AL6 1AMZ ... [ALL]
||Karpusas M., Branchaud B., Remington S.J.
||Proposed mechanism for the condensation reaction of citrate synthase: 1.9-A structure of the ternary complex with oxaloacetate and carboxymethyl coenzyme A.
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