Figure 8.

Bio-Gel P-4 profiles of uronic acids released from mature-green cv Ailsa Craig cell walls by PG2 in the presence of EDTA or Ca²⁺. Cell walls (5 mg) in 2 mL of 20 mm KOAc and 100 mm KCl were incubated for 2 h at 34°C. Shown are uronic acids released at pH 4.5 and 1.5 mm CaCl₂ (A) and at pH 6.0 and 2 mm EDTA (B). Total uronic acids in each fraction were determined at A₅₂₀ (Abs 520nm).