Yeast pyruvate carboxylase: Identification of two genes encoding isoenzymes

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Abstract

In Saccharomyces cerevisiae, pyruvate carboxylase [EC 6.4.1.1] has an important anaplerotic role in the production of oxaloacetate from pyruvate. We report here the existence of two pyruvate carboxylase isozymes, which are encoded by separate genes within the yeast genome. Null mutants were constructed by one step gene disruption of the characterised PYC gene in the yeast genome. The mutants were found to have 10–20% residual pyruvate carboxylase activity, which was attributable to a protein of identical size and immunogenically related to pyruvate carboxylase. Immunocytochemical labelling studies on ultrathin sections of embedded whole cells from the null mutants showed the isozyme to be located exclusively in the cytoplasm. We have mapped the genes encoding both enzymes and shown the previously characterised gene, designated PYC1, to be on chromosome VII whilst PYC2 is on chromosome II.

References (28)

  • F. Lim et al.

    Arch. Biochem. Biophys

    (1987)
  • H. van Urk et al.

    Biochem. Biophys. Acta

    (1989)
  • R.E. Barden et al.

    J. Biol. Chem

    (1972)
  • C.P. Morris et al.

    Biochem. Biophys. Res. Commun

    (1987)
  • F. Lim et al.

    J. Biol. Chem

    (1988)
  • M. Mandel et al.

    J. Mol. Biol

    (1970)
  • D.R. Cryer et al.
  • R.J. Rothstein

    Methods Enzymol

    (1983)
  • J.R. Broach et al.

    Gene

    (1979)
  • D.C. Schwartz et al.

    Cell

    (1984)
  • M.M. Bradford

    Anal. Biochem

    (1976)
  • C. Dijkema et al.

    Biochem. Biophys. Acta

    (1987)
  • J.C. Wallace
  • S.A. Osmani et al.

    Eur. J. Biochem

    (1983)
  • Cited by (0)

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