FIG. 2.

Inhibition of XI from C. phytofermentans (A) and Piromyces sp. strain E2 (B) by xylitol. Strains carrying the gene for XI from C. phytofermentans or Piromyces sp. strain E2, respectively, on a multicopy vector were grown as shake-flask cultures at 30°C into the exponential growth phase in synthetic medium with 20 g liter⁻¹ glucose and without uracil. Crude extracts were prepared, and quantitative enzyme activity tests were performed. Symbols: •, 0 mM xylitol; ▪, 10 mM xylitol; ▴, 30 mM xylitol; ▾, 50 mM xylitol.