Figure 2.—

External adenine affects growth and nucleotide pools of AMP deaminase-deficient strains. (A) Growth of wild-type and amd1 spores in the absence or the presence of adenine. A heterozygous AMD1/amd1∷KanMX4 diploid strain was sporulated and dissected on SDcasaWU medium containing adenine (+Ade, tetrads 4–6) or not (−Ade, tetrads 1–3). “+” and “−” signs above the colonies refer, respectively, to AMD1 (+) and amd1∷KanMX4 (−) genotypes determined on the basis of sensitivity or resistance to geneticin associated with KanMX4 expression. (B and C). Intracellular nucleotide content is affected in the amd1 mutant grown in the presence of extracellular adenine. Wild-type (WT, BY4742) and amd1 mutant strains were grown in SDcasaW medium supplemented (+Ade) or not (−Ade) with external adenine. Internal adenylic (B) and guanylic (C) nucleotides were measured as previously described (Breton et al. 2008; Gauthier et al. 2008).