A light-dependent in vitro protein-synthesizing system from isolated mesophyll chloroplasts of Sorghum vulgare was characterized. Preincubation of chloroplasts in light at 25 degrees C for 1 h depleted the endogenous templates completely; such preincubated chloroplasts translated exogenously added homologous, heterologous, and synthetic templates efficiently. The fidelity of the system in trans...

Photometric evidence for a reversible, red-light induced transmission decrease in excised leaf tissue or the thalli of certain marine algae has been obtained under conditions which correspond to the occurrence of a light-induced shrinkage of chloroplasts within the cells. Evidence supporting this conclusion is: A) The kinetics of the nonspecific transmission changes are similar to those observe...

Digestion of spinach chloroplasts with pancreatic lipase or trypsin effectively uncoupled electron transport. Continued digestion led to inhibition of saturated rates of Hill reaction activity and a decrease in quantum yield. Irradiation with ultraviolet light decreased the quantum yield and inhibited Hill activity, but did not uncouple. Ascorbate-dichlorophenol-indophenol-mediated reduction of...

Some molecular phylogenies of plastid-like genes suggest that chloroplasts (the structures responsible for photosynthesis in plants and algae) might have been secondarily lost in trypanosomatid parasites. Chloroplasts are present in some euglenids, which are closely related to trypanosomatids, and it has been argued that chloroplasts arose early in the diversification of the lineage Euglenozoa,...

Dynamic tubular extensions from chloroplasts called stromules have recently been shown to connect with nuclei and function during innate immunity. We demonstrate that stromules extend along microtubules (MTs) and MT organization directly affects stromule dynamics since stabilization of MTs chemically or genetically increases stromule numbers and length. Although actin filaments (AFs) are not re...

In saturating light radish seedlings grown in high-light growth conditions (90 W • n r 2) possess a much higher photosynthetic capacity on a chlorophyll and leaf area basis than the low-light grown plants (10 W • m-2). The higher C 0 2-fixation rate of HL-plants is due to the presence of HL-chloroplasts which possess a different ultrastructure and also different levels of the individual chlorop...

Bienertia sinuspersici is a land plant known to perform C(4) photosynthesis through the location of dimorphic chloroplasts in separate cytoplasmic domains within a single photosynthetic cell. A protocol was developed with isolated protoplasts to obtain peripheral chloroplasts (P-CP), a central compartment (CC), and chloroplasts from the CC (C-CP) to study the subcellular localization of photosy...

Toc159, a protein located in the outer envelope membrane and the cytosol, is an important component of the receptor complex for nuclear-encoded chloroplast proteins. We investigated the molecular mechanism of protein import into chloroplasts by atToc159 using the ppi2 mutant, which has a T-DNA insertion at atToc159, shows an albino phenotype, and does not survive beyond the seedling stage due t...

Chloroplasts isolated by methods similar to that described by Arnon et al. (1) are capable of incorporating acetate carbon into both lipid and n)on-lipid materials when fortified with appropriate cofactors (2, 3,4, 5). The actual rate of incorporation of acetate carbon in these preparations was, however, very small compared with the normal rate of photosynthesis (1-2 jumoles/mg chlorophyll'hr) ...

Two proteins which have carbonate dehydratase (carbonic anhydrase, EC 4.2.1.1) activity were shown to be in the chloroplasts and in the cytosol of leaves of Brassica chinensis, Spinacia oleracea, and in variegated leaves of Tradescantia albiflora and Hedera canariensis. The chloroplastic enzyme is smaller than the one in the cytosol, as it runs farther on gradient polyacrylamide gels. It was se...