FIG. 3.

Immunological detection and quantification of different l-arabinose isomerases in crude extracts of recombinant S. cerevisiae strains. Strains carrying the genes for the different l-arabinose isomerases on multicopy vectors were grown as shake flask cultures at 30°C to exponential growth phase in synthetic medium with 10 g liter⁻¹ maltose and without histidine. Crude extracts were prepared, and 20 μg of total protein was applied in each lane. Western blotting was performed as described in Materials and Methods. Lanes: 1, empty vector (p423H7); 2, YEparaA^{B. subtilis}-6HIS; 3, YEparaA^{C. aceto}-6HIS; 4, YEparaA^{B. liche}-6HIS. The arrow indicates the respective His-tagged isomerases cross-reacting with the antibodies.