scholarly journals An Electron Donor System For Nitrogenase-Dependent Acetylene Reduction by Extracts of Soybean Nodules

1968 ◽  
Vol 43 (9) ◽  
pp. 1458-1460 ◽  
Author(s):  
Robert V. Klucas ◽  
Harold J. Evans
2014 ◽  
Vol 26 (31) ◽  
pp. 315004 ◽  
Author(s):  
Stefano Prada ◽  
Livia Giordano ◽  
Gianfranco Pacchioni
Keyword(s):  

2019 ◽  
Vol 294 (34) ◽  
pp. 12708-12716 ◽  
Author(s):  
Rajib Sengupta ◽  
Lucia Coppo ◽  
Pradeep Mishra ◽  
Arne Holmgren

Weed Science ◽  
1972 ◽  
Vol 20 (4) ◽  
pp. 357-363 ◽  
Author(s):  
Charles E. Stanger ◽  
Arnold P. Appleby

Chloroplasts isolated from spinach(Spinacia oleraceaL.) leaves were used to study mechanisms of toxicity from 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron). Light was needed to initiate diuron injury. The addition of ascorbate plus 2,6-dichlorophenylindolephenol (DPIP) as an electron donor system completely protected the chloroplasts from diuron-induced toxicity. The protective effect from the electron donor system occurred only in functional chloroplasts. Diuron caused rapid and extensive chlorophyll degradation at chlorophyll: diuron ratios of 200:1 and lower. At higher ratios the effect was much less measurable. The electron donor system gave complete protection in the presence of methylamine HCl, a known inhibitor of photophosphorylation, indicating that a deficiency of ATP was not the primary cause of diuron toxicity. Time-course studies showed that carotenoid pigments began to degrade before initiation of chlorophyll degradation. These results are interpreted as supporting a hypothesis that diuron induces phytotoxicity by catalyzing lethal photosensitized oxidations in the cell. This may occur as a result of (a) a greater concentration of oxidized chlorophyll caused by an interruption of electron flow and (b) an inhibition of NADPH formation which is necessary to maintain a functional carotenoid protective mechanism.


1975 ◽  
Vol 30 (9-10) ◽  
pp. 622-627 ◽  
Author(s):  
Alfons Radunz ◽  
Georg H. Schmid

Antibodies to neoxanthin agglutinate stroma-free swellable chloroplasts from tobacco (Nico-tiana tabacum var. John William’s Broadleaf) and Antirrhinum (Antirrhinum majus) whereas stroma-freed chloroplasts, which have lost the swellability are not agglutinated despite the fact that antibodies to neoxanthin are specifically adsorbed. In this latter case the agglutination is hindered for sterical reasons. From this it is concluded that neoxanthin is located in the outer surface of the thylakoid membrane. The antiserum to neoxanthin inhibits the ferricyanide photo­ reduction in chloroplasts when water is the electron donor by 15%. With diphenylcarbazide in tris-treated chloroplasts no inhibition is observed. Hence, just as in the case of the antiserum to lutein the site of inhibition is on the donor side of potosystem II namely between water and the site of electron donation of diphenylcarbazide. Benzidine/ascorbate is another artificial electron donor system of photosystem II reported in the literature. The photoreduction of anthraquinone-2-sulphonate with this donor system is inhibited. In contrast to the antiserum to lutein the antiserum to neoxanthin inhibits DCMU-sensitive photophosphorylation reactions in the system H2O → ferricyanide and benzidine/ascorbate → anthraquinone-2-sulphonate. Therefore, the electron transport coupled to photophosphorylation is inhibited by the antiserum.


1999 ◽  
Vol 40 (4) ◽  
pp. 801-804 ◽  
Author(s):  
Martin R. Bryce ◽  
Alexander K. Lay ◽  
Andrei S. Batsanov ◽  
Judith A.K. Howard

2013 ◽  
Vol 49 (79) ◽  
pp. 8937 ◽  
Author(s):  
Atanu Jana ◽  
Masatoshi Ishida ◽  
Kevin Cho ◽  
Sudip Kumar Ghosh ◽  
Kyuju Kwak ◽  
...  

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