Spinach chloroplast

Inhibition of valinomycin-induced swelling of intact spinach chloroplasts, spinach thylakoids, and mung bean mitochondria by FCCP, selected herbicides, and carbanilates. 

Chloroplast (spinach) Protoplast (B.megaterium) Mitochondrion (rat) Erythrocyte (rat) Myelin (rat)... 

Jagendorf, A. T, and Uribe, E., 1966. ATP formadon caused by acid-base transidon of spinach chloroplasts. Proceedings of the National Academy of Sciences, USA 55 170-177. The classic paper providing the first experimental verificadon of Mitchell s chemiosmodc hypodiesis. 

Synthesis in a Cell-free Extract of Spinach Chloroplasts. 277... 

An extract from the soluble stromal proteins of purified and intact spinach-leaf chloroplasts was prepared by lysis of the cells in buffer, centrifugation of the suspension of broken cells, and concentration of the supernatant with removal of insoluble material. This extract contained all of the enzymes involved in the condensation of the cyclic moieties of thiamine, thiazole, and pyramine. Thus, the synthesis of thiamine in this extract following the addition of pyramine and putative precursors was a proof that the system had the possibility of building the thiazole. It was found that L-tyrosine was the donor of the C-2 carbon atom of thiazole, as in E. coli. Also, as in E. coli cells, addition of 1 -deoxy-D-f/irco-pen-tulose permitted synthesis of the thiamine structure. The relevant enzymes were localized by gel filtration in a fraction covering the 50- to 350-kDa molecular-mass range. This fraction was able to catalyze the formation of the thiazole moiety of thiamine from 0.1 -mM 1-deoxy-D-t/ireo-pentulose at the rate of 220 pmol per mg of protein per hour, in the presence of ATP and Mg2+. 

Spinach chloroplasts There is some evidence that pyramine originates from AIR.80... 

During the 1960s, research on proteins containing iron—sulfur clusters was closely related to the field of photosynthesis. Whereas the first ferredoxin, a 2[4Fe-4S] protein, was obtained in 1962 from the nonphotosynthetic bacterium Clostridium pasteurianum (1), in the same year, a plant-type [2Fe-2S] ferredoxin was isolated from spinach chloroplasts (2). Despite the fact that members of this latter class of protein have been reported for eubacteria and even archaebacteria (for a review, see Ref. (3)), the name plant-type ferredoxin is often used to denote this family of iron—sulfur proteins. The two decades... 

The prototype of this class of soluble ferredoxins was initially obtained from spinach chloroplasts and subsequently been shown to play a role in physiological electron shuttling between PSl and a number of redox proteins, most prominently ferredoxin-NADP-reduc-tase 13). Homologous proteins were purified from several cyanobac-... 

A decade after the discovery of the Rieske protein in mitochondria (90), a similar FeS protein was identified in spinach chloroplasts (91) on the basis of its unique EPR spectrum and its unusually high reduction potential. In 1981, the Rieske protein was shown to be present in purified cytochrome Sg/complex from spinach (92) and cyanobacteria (93). In addition to the discovery in oxygenic photosynthesis, Rieske centers have been detected in both single-RC photosynthetic systems [2] (e.g., R. sphaeroides (94), Chloroflexus (95)) and [1] (Chlo-robium limicola (96, 97), H. chlorum (98)). They form the subject of a review in this volume. 

Fig. 5. Structural comparison of the water-soluble fragments of the Rieske proteins from (a) spinach chloroplasts and (b) beef heart mitochondria. Conserved smd vEiriable regions are highlighted and the conserved /3-loop discussed in Fig. 6 is denoted by darker gray on the rear of the molecules.

Fig. 6. Sequence comparisons of Rieske proteins from spinach chloroplasts, beef heart mitochondria, green sulfur bacteria, and firmicutes. The extended insertion of proteobacterial Rieske proteins as compared to the mitochondrial one is indicated by a dotted arrow. The redox-potential-influencing Ser residue is marked by a vertical arrow. The top and the bottom sequence numberings refer to the spinach and bovine proteins, respectively. Fully conserved residues are marked by dark shading, whereas the residues conserved in the b6f-group are denoted by lighter shading.

Asada, K., Kiso, K. Toshikawa, K. (1974). Univalent reduction of molecular oxygen by spinach chloroplasts on illumination. Journal of Biological Chemistry, 249, 2175-81. 

Weigel, P., Lerma, C. Hanson, A.D. (1988). Choline oxidation by intact spinach chloroplasts. Plant Physiology, 86, 54-60. 

The discovery by Knaff and Amon(32) of a light-induced photooxidation at — 189°C requiring short-wavelength light has provided information as to a possible primary electron donor for Sn. The photooxidized substance has been identified as a form of cytochrome b absorbing at 559 nm (cytochrome 559)- Pretreatment of the spinach chloroplasts with ferricyanide to oxidize... 

Aman, R., A. Schieber, and R. Carle. 2005a. Effects of heating and illumination on trans-cis isomerization and degradation of (3-carotene and lutein in isolated spinach chloroplasts. J. Agric. Food Chem. 53 9512-9518. 

Harbour, J.R. and Bolton, J.R. 1975. Superoxide formation in spinach chloroplasts electron spin resonance detection by spin trapping. Biochemical and Biophysical Research Communications 64 803-807. 

Work by Harbour, Chow and Bolton (1974) on the spin adducts of superoxide (or HOO )13 with nitrones paved the way for a number of investigations of superoxide and hydroperoxyl radical chemistry. Harbour and Bolton (1975) used DMPO to trap superoxide formed by spinach chloroplasts in the presence of 02. The signal strength was greatly enhanced when methylviologen was present, consistent with the hypothesis that this bis-pyridinium dication accepts an electron from the primary acceptor of photoprotein I, and then transfers it to molecular oxygen. 

Achnrne L, Pereda-Miranda R, Iglesias-Prieto R, Moreno-Sanchez R, Lotina-Hennsen B (1999) Tricolorin A, a Potent Natural Uncoupler and Inhibitor of Photosystem II Acceptor Side of Spinach Chloroplasts. Physiol Plant 106 246... 

Bromacil and isocil have been found to be potent and specific inhibitors of photosynthesis at the chloroplast level [361]. The uptake of carbon dioxide is blocked in Chlorella pyrenoidosa and growth inhibition parallels the inhibition of carbon dioxide uptake. In Euglena gracilis and in spinach chloroplasts, the blockage of oxygen production was noted [361]. 

Table II Inhibition of Hill Reaction in Spinach Chloroplasts...

It will be noted that in isolated spinach chloroplasts, one hardly needs to worry about making an inhibitor too hydrophobic i.e. optimal log P = 5.2 for the N,N-dimethyl- and 5.4 for the methoxymethyl-ureas. In contrast to the isolated chloroplast studies, one sees from a list of commercially successful herbicides for which log P values have been measured or calculated, (Table IV) that getting the herbicide to the chloroplast in the living plant places much greater restrictions on its hydrophobic-hydrophilic balance. Indeed, the average log P of this set is only 2.54. 

Other orchid metabolites suchs as batatasin 1, inhibited the growth of liverworts, algae and oat coleoptiles. Batatasin 1 also inhibited the CO2 dependent O2 evolution and the flow of electrons from water to methylvi-ologen in spinach chloroplasts, and it inhibited the succinate-dependent O2 uptake in potato tuber mitochondria. Other phenanthrenes such as orchinol, which has a free hydroxyl at the 7-position, inhibit indole-3-acetic acid (lAA) oxidation catalyzed by horseradish peroxidase. 

Chloroplasts. Intact chloroplasts were isolated from freshly harvested growth chamber-grown spinach (Splnacla oleracea L.) as described by Lilley and Walker (10). Thylakoids were prepared by the method of Armond t al. (11). Chlorophyll concentrations were determined by the method of MacKinney (12). Photochemical reactions yere conducted at 25°C with a photon fluence rate of 750... 

Chloroplast and thylakold responses. In exploratory studies, all of the allelochemicals inhibited C02 dependent 0 evolution of intact spinach chloroplasts. values for the six representative... 

Chloroplasts, of Coupled Electron Transport and Phosphorylation, and of Uncoupled Electron Transport by Spinach Thylakoids... 

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