Article

Identification by bacterial expression and functional reconstitution of the yeast genomic sequence encoding the mitochondrial dicarboxylate carrier protein

{ "0" : "The M.R.C. Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK" , "1" : "Department of Pharmaco-Biology, Laboratory of Biochemistry and Molecular Biology, University of Bari, Via Orabona 4, 70125 Bari, Italy" , "3" : "Dicarboxylate carrier" , "4" : "Transport" , "5" : "Mitochondria"}
FEBS Letters (impact factor: 3.54). 01/1997; DOI:10.1016/S0014-5793(96)01350-6

ABSTRACT The inner membranes of mitochondria contain a family of transport proteins of related sequence and structure. The DNA sequence of the genome of Saccharomyces cerevisiae encodes at least 35 members of this family. Three of them can be recognised as known isoforms of the ADP-ATP translocase and two others as the phosphate and citrate carriers. The transport functions of the remainder cannot be identified with certainty. One of them, encoded on yeast chromosome xii, shows a fairly close sequence relationship to the known sequence of the bovine mitochondrial oxoglutarate-malate carrier. The yeast protein has been obtained by over-expression in Escherichia coli, reconstituted into phospholipid vesicles and shown to have transport properties characteristic of the mitochondrial carrier for dicarboxylate ions, such as malate, and also phosphate, previously biochemically characterised, but not sequenced, from both mammalian and yeast mitochondria. This is the first example of the biochemical identification of an unknown membrane protein encoded in the yeast genome since the completion of the genomic sequence.

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Keywords

ADP-ATP translocase
 
biochemically characterised
 
bovine mitochondrial oxoglutarate-malate carrier
 
citrate carriers
 
dicarboxylate ions
 
DNA sequence
 
first example
 
genomic sequence
 
inner membranes
 
known sequence
 
malate
 
mitochondrial carrier
 
reconstituted
 
Saccharomyces cerevisiae encodes
 
sequenced
 
transport functions
 
transport properties characteristic
 
unknown membrane protein encoded
 
yeast genome
 
yeast mitochondria