Applied Biochemistry and Biotechnology

, Volume 77, Issue 1, pp 311–316

l-Asparaginase II of Saccharomyces cerevisiae

Activity profile during growth using an ure 2 mutant P40-3C and a P40-3C+URE2p strain
  • Edna M. M. Oliveira
  • Elvira Carvajal
  • Elba P. S. Bon
Article

DOI: 10.1385/ABAB:77:1-3:311

Cite this article as:
Oliveira, E.M.M., Carvajal, E. & Bon, E.P.S. Appl Biochem Biotechnol (1999) 77: 311. doi:10.1385/ABAB:77:1-3:311

Abstract

The activity profile of the periplasmic asparaginase of Saccharomyces cerevisiae was determined during cell growth in an ure2 mutant; in an ure2 transformed with a plasmid containing the gene URE2 and, for comparison, in the strain D273-10B. Cells were cultivated in media presenting variable quantitative and qualitative nitrogen availability and the enzyme activity was evaluated in fresh and in nitrogen-starved cells. Nitrogen affected the asparaginase II level in fresh and starved cells of all strains. In the best condition, enzyme was produced by the wild-type cells at the late log-phase in the glucose/ammonium medium with a carbon to nitrogen ratio 4.3:1. Upon starvation, the activity doubled. The overall profile of the transformed strain was similar to that of the wild-type strain. In the ure2 mutant, highenzyme levels were observed during growth, as expected. However the activity level, upon starvation, in proline grown cells, increased sixfold, suggesting that in addition to the Ure2p-Gln3p system, another system regulates asparaginase II biosynthesis.

Index Entries

Saccharomyces cerevisiaeURE2 proteinnitrogen regulationl-asparaginase IInitrogen nutrition

Copyright information

© Humana Press Inc. 1999

Authors and Affiliations

  • Edna M. M. Oliveira
    • 1
  • Elvira Carvajal
    • 2
  • Elba P. S. Bon
    • 1
  1. 1.Departmento de Bioquímica, Instituto de QuímicaUniversidade Federal do Rio de JaneiroRio de JaneiroBrazil
  2. 2.Departmento de Biologia Celular e Genética, Instituto de BiologiaUniversidade do Estado do Rio de JaneiroRio de JaneiroBrazil