Figure 1.

Purification of peroxisomes from pea leaves. Cell organelles were purified from 50-d-old pea leaves by differential and Suc density-gradient centrifugations, as described by López-Huertas and co-workers (1995). Gradient fractions of 1.5 mL were eluted with a gradient fractionator and assayed for specific marker enzymes to localize cell organelles in the gradient: fumarase for mitochondria and catalase for peroxisomes. Catalase and fumarase activities are expressed in μmol min⁻¹ mL⁻¹ and NADP-ICDH activity in milliunits mL⁻¹. Proteins were expressed as mg mL⁻¹ and density as g cm⁻³. Top: ●, Proteins; ○, density. Middle: ●, Catalase; ○, fumarase. Bottom: NADP-IDH.