Figure 5

The effects of H ₂ O ₂ , GvP1 extensin and EIBMPs on primary cell wall hydration. A) The effect of H₂O₂ on native cell wall (NCW) hydration. B) Extracellular, ionically binding matrix proteins (EIBMPs) influence the effect of H₂O₂ on cell wall hydration. Saline extracted, native cell walls (treatment 1; T1) were used as the starting material for these experiments. Hydration measurements are presented as % hydration of native cell walls ± s.d. Each data point was calculated from the average of 4 samples, each measured in triplicate. Incubation with H₂O₂ was for 0.5 h, unless otherwise indicated. Amounts of saline-soluble GvP1 (μg.mg^-1 cell wall [FW]) after treatments is indicated within each bar. Student t-test was used to identify significant (p ≤ 0.01) differences between hydration values. Key: Successive '+' symbols describe the order of treatments except those enclosed by brackets which were made simultaneously; SE = saline extraction; EIBMP^a = endogenous levels of whole EIBMPs; EIBMP^b = 2 × endogenous levels of whole EIBMPs; EIBMP^c = GvP1-free EIBMPs fractionated from native cell walls.