C3 or crassulacean acid metabolism (CAM)-induced Mesembryanthemum crystallinum plants perform nocturnal starch degradation which is linear with time. To analyse the composition of metabolites released by isolated leaf chloroplasts during starch degradation we developed a protocol for the purification of starch-containing plastids. Isolated chloroplasts from C3 or CAM-induced M. crystallinum pla...

A NUMBER of references to experiments conducted with isolated chloroplasts are to be found in the literature. Englemann [1881] detected the evolution of oxygen by isolated chloroplasts and Ewart [1896] observed that they maintained their activity for some time after removal from the cell. Chloroplasts have been isolated from Stellaria media by Hill [1937] and from the leaves of the tomato plant...

The spatial organization of chloroplast DNA in developing and dividing wheat chloroplasts was studied in the light microscope using the fluorescent probe 4'-6-diamidino-2-phenylindole, which binds specifically to DNA.The DNA of wheat chloroplasts was localized at the periphery of the plastid, frequently in a discrete band. No relocalization of the DNA was observed during plastid replication. Th...

Incubation of synthetic 12-hydroxy-(3Z)-dodecenal (3ZHD) with tea chloroplasts revealed that 12-hydroxy-(2£)-dodecenal (2EHD) was the product of isomerization reaction of 3ZHD during the incubation. The isomerization was caused also by incubation of 3ZHD with the heat-inactivated chloroplasts. The isomerization activity was extracted with hot ethanol. These results indicate that the isomerizati...

Preprotein translocation across the outer and inner envelope membranes of chloroplasts is an energy-dependent process requiring ATP hydrolysis. Several precursor proteins analyzed so far have been found to be imported into isolated chloroplasts equally well in the dark in the presence of ATP as in the light where ATP is supplied by photophosphorylation in the chloroplasts themselves. We demonst...

Intact chloroplasts of spinach (Spinacia oleracea L.), sunflower (Helianthus annuus L.), and maize (Zea mays L.) mesophyll cells contained 0.33, 0.50, and 0.14% of bound hexosamine on a protein basis, respectively. Undifferentiated maize chloroplasts contained 0.19%. Values for chloroplast lamellae were, respectively, 0.16, 0.18, 0.12, and 0.06% and for envelope membranes they were 1.6, 2.5, 3....

Mitochondria and chloroplasts are major sources of free radical generation in living organisms. Because of this, these organelles require strong protection from free radicals and associated oxidative stress. Melatonin is a potent free radical scavenger and antioxidant. It meets the criteria as a mitochondrial and chloroplast antioxidant. Evidence has emerged to show that both mitochondria and c...

Fig. 1. Typical intracellular distribution pattern of chloroplasts by their photorelocation movement. In darkness, chloroplasts are located on the cell bottom in Arabidopsis thaliana. Note that the dark position varies among plant species. Weak light induces the chloroplast accumulation response along the peliclinal walls so that chloroplasts can perceive light efficiently. Strong light induces...

Sedimentation and electron microscopic studies have provided no evidence for the presence of circular DNA (deoxyribonucleic acid) in chloroplasts from wheat leaves. Electron microscopy of osmotically disrupted chloroplasts has revealed the presence of linear duplex filaments, some with a tertiary helicoidal configuration and possibly monostranded filaments. None of these structures was observed...