Table 5.

Grr1p and Uga35p are essential to the transcriptional induction of the AGP1 genea

Line no.Nitrogen sourcesAGP1-lacZβ-galactosidase activity (nmol · min−1 · mg of protein−1)
Wild typegrr1Δuga35Δ
 2Urea + Leu638≤2
 3Urea + IIe895≤2
 4Urea + Phe960≤2
 5Urea + Tyr724≤2
 6Urea + Met744≤2
 7Urea + citrulline284≤2
 9Proline + Leu83918
 10Proline + IIe1,2278
 11Proline + Phe1,34310
 12Proline + Tyr7915
 13Proline + Met95011
 14Proline + citrulline235≤2
  • a Strains 23344c (ura3), JA115 (grr1Δ ura3) and CD17 (uga35Δura3) transformed by the CEN-based YCpAGP1-lacZplasmid were grown on minimal medium with the indicated compounds as the sole nitrogen source(s), each added at a 5 mM concentration. Theuga35Δ was grown on proline instead of urea medium because of its inability to use urea as the sole nitrogen source. The reported β-galactosidase activities are means of two to three independent experiments. Variations were less than 20%.