Figure 6.

Immunoblot analyses of HMGR-containing fractions derived from leaf samples (5-week-old plants) separated in Suc density gradients. A, Fractionation of P16 in a 35% to 55% (w/v) Suc density gradient. Thirty microliters of every other fraction (1–19) were loaded in each well of SDS gels. The plastid-containing fractions are indicated by boxes above the corresponding lanes, where the different shades of gray are proportional to the amount of chlorophyll determined spectrophotometrically. B, Fractionation of S16 in a 20% to 40% (w/v) Suc density gradient. Thirty microliters of every other fraction (1–19) were loaded in each well of SDS gels. PVDF membranes representing each gradient were incubated first with anti-CD1 antiserum (top blots), polypeptides were detected, and then the blots were incubated with anti-FPS1 antiserum (middle blots) and polypeptides detected again. For catalase detections (bottom blots), separate gels were loaded, electroblotted, and immunodetected for catalase polypeptides (approximately 57 kD).