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Saccharomyces cerevisiae (Sc) citrate synthases Cit1-2_like. Citrate synthases (CS) catalyzes the condensation of acetyl coenzyme A (AcCoA) with oxaloacetate (OAA) to form citrate and coenzyme A (CoA), the first step in the citric acid cycle (TCA or Krebs cycle). Some CS proteins function as 2-methylcitrate synthase (2MCS). 2MCS catalyzes the condensation of propionyl-coenzyme A (PrCoA) and OAA to form 2-methylcitrate and CoA during propionate metabolism. The overall CS reaction is thought to proceed through three partial reactions and involves both closed and open conformational forms of the enzyme: a) the carbanion or equivalent is generated from AcCoA by base abstraction of a proton, b) the nucleophilic attack of this carbanion on OAA to generate citryl-CoA, and c) the hydrolysis of citryl-CoA to produce citrate and CoA. There are two types of CSs: type I CS and type II CSs. Type I CSs are found in eukarya, gram-positive bacteria, archaea, and in some gram-negative bacteria and are homodimers with both subunits participating in the active site. Type II CSs are unique to gram-negative bacteria and are homohexamers of identical subunits (approximated as a trimer of dimers). ScCit1 is a nuclear-encoded mitochondrial CS with highly specificity for AcCoA. In addition to its CS function, ScCit1 plays a part in the construction of the TCA cycle metabolon. Yeast cells deleted for Cit1 are hyper-susceptible to apoptosis induced by heat and aging stress. ScCit2 is a peroxisomal CS involved in the glyoxylate cycle; in addition to having activity with AcCoA, it may have activity with PrCoA. Chicken and pig heart CS, two Arabidopsis thaliana (Ath) CSs, CSY4 and -5, and Aspergillus niger (An) CS also belong to this group. Ath CSY4 has a mitochondrial targeting sequence; AthCSY5 has no identifiable targeting sequence. AnCS encoded by the citA gene has both an N-terminal mitochondrial import signal and a C-terminal peroxisiomal target sequence; it is not known if both these signals are functional in vivo. This group contains proteins which functions exclusively as either a CS or a 2MCS, as well as those with relaxed specificity which have dual functions as both a CS and a 2MCS.
No pairwise interactions are available for this conserved domain.
Tips:  If you've navigated here from a protein, hovering over a position on the weblogo will display the corresponding protein position for that domain position. The histograms below the weblogo indicate mutations found on the domain. Red is for disease (OMIM) and blue is for SNPs. Functional Features are displayed as orange boxes under the histograms. You can choose which features are displayed in the box below. Range on the Protein: Protein ID Protein Position Domain Position: 
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