FIG. 6.

Uptake and hydrolysis of sucrose by X. axonopodis pv. glycines. (A) Time courses of sucrose uptake by strain 8ra (solid circles) and the suh mutant (open circles). Sucrose uptake was monitored by measuring the radioactivity of cells exposed to [U-¹⁴C]sucrose at ambient temperature. The data are expressed as amounts of sucrose (in nanomoles) taken up by cells in 0.2 ml of suspension at an OD₆₀₀ of 2. (B) TLC profiles of sugars contained in 18-h incubations of sucrose (50 mM) with crude protein extracts (0.6 mg of protein/ml) at 30°C. The extracts were from the 8ra cells grown on glucose (lane 1), fructose (lane 2), and sucrose (lane 3) and from suh mutant cells grown on sucrose (lane 4). A mixture of sugar standards (F, fructose; G, glucose; S, sucrose; 0.1 μmol each) was also developed (lane S).