Continuous labelling of callus with H-thymidine results in intermittent peaks of H-DNA per chloroplast, showing synchrony of division. The increase in H-DNA could be due to several replication rounds, and the drop to successive plastid divisions without intervening DNA synthesis. The level of DNA-binding proteins in the chloroplast parallels the peaks of plastidal DNA synthesis; such pro...

continuous labelling of callus with h-thymidine results in intermittent peaks of h-dna per chloroplast, showing synchrony of division. the increase in h-dna could be due to several replication rounds, and the drop to successive plastid divisions without intervening dna synthesis. the level of dna-binding proteins in the chloroplast parallels the peaks of plastidal dna synthesis; such proteins c...

a restriction-site analysis of chloroplast dna (cpdna) was carried out to evaluate the levelof diversity in vicia faba l. germplasm selected from different geographical regions using 11 restrictionendonucleases. we analyzed 214 restriction sites in 18 accessions of vicia faba. all of the accessionshad identical cpdnas, pointing out the ancestral character of all the accessions are of only one g...

Chloroplasts arose from a cyanobacterial endosymbiont and multiply by division. In algal cells, chloroplast division is regulated by the cell cycle so as to occur only once, in the S phase. Chloroplasts possess multiple copies of their own genome that must be replicated during chloroplast proliferation. In order to examine how chloroplast DNA replication is regulated in the green alga Chlamydom...

The isolation of chloroplast and nuclear DNA from dark- and light-grown, control- and 3-amino-1,2,4-triazole-treated wheat seedlings, Triticum vulgare, is described. Contrary to a previous report, we found that chloroplast and nuclear DNA had similar buoyant densities (1.702 grams per cubic centimeter) and that they could not be resolved by buoyant density centrifugation in CsCl. Difference in ...

The number of chloroplast DNA molecules in Euglena gracilis cells was measured by determining the shift in the observed second-order rate constant for the reassociation of (125)I-labeled chloroplast DNA in the presence of unlabeled total cell DNA. Cells grown to stationary phase in the dark contained 217 molecules of chloroplast DNA. Cells grown to stationary phase in the light in either hetero...

The effect of rifampin, an inhibitor of bacterial DNA-dependent RNA polymerase, was studied in Chlamydomonas reinhardi. It was shown, in vivo and in vitro, that chloroplast-located, but not nuclear, DNA-dependent RNA polymerase is inhibited by this drug. The inhibition of chloroplast RNA polymerase results in the inhibition of chloroplast rRNA synthesis, and thus in the loss of chloroplast ribo...

Triton X-100 solubilized chloroplast DNA but not nuclear DNA from a mixture of chloroplasts and nuclei. The buoyant density of chloroplast DNA was different from that of the satellite DNA in all of the species examined (Phaseolus coccineus, Cucumis sativus, Cucumis melo, Antirrhinum majus, Vicia faba, Oenothera fruiticosa youngii). Chloroplast DNA constituted between 4.3% and 0.25% of the total...

A DNA binding protein with DNA polymerase 'accessory activity' has been identified and purified to apparent homogeneity from pea chloroplasts. This protein consists of a single subunit of 43 kDa and binds to DNA regardless of its base sequence and topology. It increases cognate DNA polymerase-primase activity in a dose dependent manner. Using solid phase protein-protein interaction trapping and...

BACKGROUND Obtaining chloroplast genome sequences is important to increase the knowledge about the fundamental biology of plastids, to understand evolutionary and ecological processes in the evolution of plants, to develop biotechnological applications (e.g. plastid engineering) and to improve the efficiency of breeding schemes. Extraction of pure chloroplast DNA is required for efficient seque...