Regulation of Nitrate Reductase in the Basidiomycete Ustilago maydis

AUTOR(ES)

Lewis, C. M.

RESUMO

Nitrate reductase was induced in Ustilago maydis by growth in medium containing only nitrate as the nitrogen source. Ammonium ions repressed the enzyme and led to a rapid loss of activity. Ammonium did not inhibit the enzyme in vitro; although amino acids partially did so, this cannot account for the rapid loss of in vivo activity which occurred when the ammonium was added. Experiments with cycloheximide and actinomycin D, together with measurements of protein turnover, suggested that nitrate reductase is actively broken down when cells with fully induced activity are transferred to medium containing ammonium ions.

Documentos Relacionados

• The gene coding for small ribosomal subunit RNA in the basidiomycete Ustilago maydis contains a group I intron.
• Suppression of the Killer Phenotype in USTILAGO MAYDIS
• Nitrate Reductase mRNA Regulation in Nicotiana plumbaginifolia Nitrate Reductase-Deficient Mutants.
• The a locus governs cytoduction in Ustilago maydis.
• Biochemical Mutants in the Smut Fungus Ustilago Maydis