TABLE 2.

Expression of a transcriptional fusion lamB–lacZ

Genotype	DM250 glucose	DM250 maltose
606	100.00	219.24 ± 3.55
606 malT Ara−1	12.99 ± 0.78	214.33 ± 2.36
606 malT Ara+1	1.22 ± 0.61	NA

β-Galactosidase activities of ancestral strains with the evolved malT alleles from population Ara − 1 (606 malT ^Ara−1) and population Ara + 1 (606 malT ^Ara+1) are expressed relative to the specific activity measured for the isogenic strain carrying the ancestral malT allele (606), which is arbitrarily set to the value of 100 for growth in DM250 glucose. The strains were grown overnight in DM250 containing glucose or maltose as the sole carbon source. NA, not applicable because this strain did not grow in DM250 maltose.