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  • The EMBO Journal (1998) 17, 4257 - 4265
  • doi:10.1093/emboj/17.15.4257

The Pdr12 ABC transporter is required for the development of weak organic acid resistance in yeast

Peter Piper1,5, Yannick Mahé2,3,5, Suzanne Thompson1, Rudy Pandjaitan2, Caroline Holyoak4, Ralf Egner2, Manuela Mühlbauer2, Peter Coote4 and Karl Kuchler2

  1. Department of Biochemistry and Molecular Biology, University College London, London WC1E 6BT, UK
  2. Department of Molecular Genetics, University and Biocenter of Vienna, A-1030 Vienna, Austria
  3. Present address: Institut Curie, INSERM U-248, Section de Recherche, 26, rue d'Ulm, 75248 Paris, Cedex 05, France
  4. Microbiology Department, Unilever Research, Colworth Laboratory, Sharnbrook, Bedford MK44 1LQ, UK
  5. P.Piper and Y.Mahé contributed equally to this work

Correspondence to:

Karl Kuchler, E-mail: kaku@mol.univie.ac.at

Received 19 February 1998; Accepted 2 June 1998; Revised 19 May 1998

Exposure of Saccharomyces cerevisiae to sorbic acid strongly induces two plasma membrane proteins, one of which is identified in this study as the ATP-binding cassette (ABC) transporter Pdr12. In the absence of weak acid stress, yeast cells grown at pH 7.0 express extremely low Pdr12 levels. However, sorbate treatment causes a dramatic induction of Pdr12 in the plasma membrane. Pdr12 is essential for the adaptation of yeast to growth under weak acid stress, since Deltapdr12 mutants are hypersensitive at low pH to the food preservatives sorbic, benzoic and propionic acids, as well as high acetate levels. Moreover, active benzoate efflux is severely impaired in Deltapdr12 cells. Hence, Pdr12 confers weak acid resistance by mediating energy-dependent extrusion of water-soluble carboxylate anions. The normal physiological function of Pdr12 is perhaps to protect against the potential toxicity of weak organic acids secreted by competitor organisms, acids that will accumulate to inhibitory levels in cells at low pH. This is the first demonstration that regulated expression of a eukaryotic ABC transporter mediates weak organic acid resistance development, the cause of widespread food spoilage by yeasts. The data also have important biotechnological implications, as they suggest that the inhibition of this transporter could be a strategy for preventing food spoilage.

  • Keywords:

    • ABC protein,
    • adaptation,
    • Saccharomyces cerevisiae,
    • stress response,
    • weak organic acid tolerance