FIG. 5.

Functional analysis of A. nidulans ammonium permeases in areA mutant backgrounds. (A) Growth on a range of ammonium concentrations of areAΔ (MH5699), areAΔ mepAΔ (MH10313), areAΔ meaAΔ (MH10311), and areAΔ meaAΔ mepAΔ (MH10314) mutant and wild-type (MH1) strains. For each ammonium concentration, the pH of the medium was either 4.5 or 6.5 (normal growth pH), as indicated. Growth on nitrogen-free (−), 10 mM alanine (ala), GABA, nitrate (NO₃⁻), and proline (pro) media is also shown. (B) [¹⁴C]methylammonium transport rates for the wild-type strain and mepAΔ, meaAΔ, meaAΔ mepAΔ, areAΔ, areAΔ mepAΔ, areAΔ meaAΔ, areAΔ meaAΔ mepAΔ, and meaAΔ mepAΔ mepBΔ mutant strains. Assays were performed with nitrogen-starved mycelia at a final methylammonium concentration of 200 μM. Error bars represent standard errors calculated for the results from at least two independent experiments.