title: Cysteine uptake by Saccharomyces cerevisiae is accomplished by multiple permeases.
abstract: Uptake by Saccharomyces cerevisiae of the sulphur-containing amino acid L-cysteine was found to be non-saturable under various conditions, and uptake kinetics suggested the existence of two or more transport systems in addition to the general amino-acid permease, Gap1p. Overexpression studies identified BAP2, BAP3, AGP1 and GNP1 as genes encoding transporters of cysteine. Uptake studies with disruption mutants confirmed this, and identified two additional genes for transporters of cysteine, TAT1 and TAT2, both very homologous to BAP2, BAP3, AGP1 and GNP1. While Gap1p and Agp1p appear to be the main cysteine transporters on the non-repressing nitrogen source proline, Bap2p, Bap3p, Tat1p, Tat2p, Agp1p and Gnp1p are all important for cysteine uptake on ammonium-based medium. Furthermore, whereas Bap2p, Bap3p, Tat1p and Tat2p seem most important under amino acid-rich conditions, Agp1p contributes significantly when only ammonium is present, and Gnp1p only contributes under the latter condition.
authors.affiliation: Carlsberg Research Laboratory, Gamle Carlsberg Vej 10, DK-2500 Copenhagen Valby, Denmark.
authors.forename: L
authors.initials: L
authors.lastname: Düring-Olsen
authors.forename: B
authors.initials: B
authors.lastname: Regenberg
authors.forename: C
authors.initials: C
authors.lastname: Gjermansen
authors.forename: M C
authors.initials: MC
authors.lastname: Kielland-Brandt
authors.forename: J
authors.initials: J
authors.lastname: Hansen
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D026905:Amino Acid Transport Systems; D026923:Amino Acid Transport Systems, Basic; D026921:Amino Acid Transport Systems, Neutral; D001692:Biological Transport / Q000187:drug effects; D003470:Culture Media / Q000494:pharmacology; D003545:Cysteine / Q000493:pharmacokinetics*; D005095:Exoribonucleases / Q000235:genetics / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D015966:Gene Expression Regulation, Fungal; D007930:Leucine / Q000494:pharmacology; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D016297:Mutagenesis, Site-Directed; D011062:Polynucleotide Adenylyltransferase; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins
chemical_list: C420623:AGP1 protein, S cerevisiae; D018528:ATP-Binding Cassette Transporters; D026905:Amino Acid Transport Systems; D026923:Amino Acid Transport Systems, Basic; D026921:Amino Acid Transport Systems, Neutral; C097094:BAP2 protein, S cerevisiae; C429560:BAP3 protein, S cerevisiae; D003470:Culture Media; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D029701:Saccharomyces cerevisiae Proteins; C429825:TAT2 protein, S cerevisiae; C075577:RAT1 protein, S cerevisiae; C051432:glutamine permease; C429559:PAP1 protein, S cerevisiae; D011062:Polynucleotide Adenylyltransferase; D005095:Exoribonucleases; D007930:Leucine; D003545:Cysteine