Molecular Structure of the Mitochondrial Citrate Transport Protein
The mitochondrial citrate transport protein (i.e., CTP) is located within the inner mitochondrial membrane and in higher eukaryotes catalyzes an obligatory 1:1 exchange of the dibasic form of a tricarboxylic acid (e.g., citrate, isocitrate, or cis-aconitate) for either another tricarboxylate, a dicarboxylate, or phosphoenolpyruvate (Palmieri et al. 1972; Bisaccia et al.1993; Palmieri 2004). The CTP occupies a prominent position within intermediary metabolism since following the efflux of citrate from the mitochondrial matrix and subsequent diffusion across the outer mitochondrial membrane, the resulting cytoplasmic citrate serves as the main carbon source fueling the fatty acid, triacylglycerol, and cholesterol biosynthetic pathways (Watson and Lowenstein 1970; Brunengraber and Lowenstein 1973; Endemann et al. 1982; Conover 1987).
KeywordsSubstrate Binding Site Dime Interface Substrate Protection Bind Site Residue Translocation Pathway
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