TABLE 2.

Apparent Km values of Tna1, Tnr1, and Tnr2 for NA, NAM, and NRa

ProteinMean Km (μM) ± SEM
NANAMNR
Tna10.59 ± 0.096.3 ± 1.7110 ± 50
Tnr1No uptake observed7.7 ± 1.21.6 ± 0.4
Tnr2No uptake observed5.5 ± 1.11.5 ± 0.4
  • a Uptake of radiolabeled precursors into a tna1 tnr1 tnr2 mutant strain (BG1442) expressing the gene for the indicated protein was measured.