Figure 4.

WceF cleaves stewartan exopolysaccharide. Enzymatic activity of WceF (1.5 μM) at 30 °C on the stewartan exopolysaccharide (1 mg ml⁻¹) analyzed by reducing end formation monitored with 3-methyl-2-benzothiazolinon-hydrazone (MBTH) (37). A, time course of reducing end increase in WceF–stewartan mixtures (red triangles) or stewartan (white circles) or WceF alone (black diamonds) in 50 mM MES, pH 5, 50 mM NaCl. B and C, reducing end formation from stewartan after 120 h incubation with WceF at varying pH values (B) or NaCl concentrations (C). All error bars show standard deviations obtained from three independent measurements.