Consequences of iron deficiency on photosynthetic and respiratory electron transport in blue-green algae

1985 ◽  
Vol 6 (3) ◽  
pp. 261-271 ◽  
Author(s):  
Gerhard Sandmann
Keyword(s):  
Electron Transport ◽  
Iron Deficiency ◽  
Green Algae ◽  
Blue Green Algae ◽  
Respiratory Electron Transport

Interaction of Photosynthetic and Respiratory Electron Transport in Blue-Green Algae: Effect of a Cytochrome c-553 Specific Antibody

1984 ◽  
Vol 39 (6) ◽  
pp. 623-626 ◽  
Author(s):  
Irene Alpes ◽  
Erwin Stürzl ◽  
Siegfried Scherer ◽  
Peter Böger
Keyword(s):  
Electron Transport ◽  
Cytochrome C ◽  
Oxygen Uptake ◽  
Green Algae ◽  
Specific Antibody ◽  
Nostoc Muscorum ◽  
Membrane Material ◽  
Specific Antibodies ◽  
Blue Green Algae ◽  
Respiratory Electron Transport

An antibody prepared against purified cytochrome c-553 from Nostoc muscorum inhibits the redox function of cytochrome c-553 as checked by a diaphorase assay. 20 to 30% inhibition of NADPH-driven respiratory and light-induced oxygen uptake by Nostoc thylakoids is observed when cytochrome c-553 specific antibodies were applied. However, only 30 to 50% of the total cytochrome c-553 content is released from isolated membrane material, thus being accessible to antibodies. Supplementing the isolated membrane material with excess Nostoc cytochrome before adding the antibody abolishes inhibition. The data provide further evidence for soluble cytochrome c-553 being a link between photosynthetic and respiratory electron transport in blue- green algae.

Fructose-Stimulated Ferrievanide Reduction by Intact Blue-Green Algae

1985 ◽  
Vol 40 (1-2) ◽  
pp. 138-141 ◽  
Author(s):  
Siegfried Scherer ◽  
Peter Boger
Keyword(s):  
Electron Transport ◽  
Oxygen Uptake ◽  
Green Algae ◽  
Transport Processes ◽  
Carbon Pool ◽  
Ferricyanide Reduction ◽  
Intact Cells ◽  
Blue Green Algae ◽  
Green Algal ◽  
Respiratory Electron Transport

Abstract As reported in the literature, ferricyanide reduction of blue-green algal cells in the dark is linked to respiratory electron transport. This study has not verified this hypothesis. There was no concurrent activity of ferricyanide reduction by intact cells with respiratory oxygen uptake. It was found light-independent, showing little KCN-inhibition, but was strongly CCCP-sensitive. CCCP inhibition was reversed by KCN. - Both, respiration and ferricyanide reduction were stimulated by fructose which was actively accumulated by the cells (the apparent K m was 20 μM). Ferricyanide reduction was more sensitive towards dark starvation than respiration. Based on these data it is suggested that ferricyanide reduction and cyanide-sensitive respiration are parts of different electron-transport processes, competing for reduction equivalents originating from the same (endogenous) carbon pool.

Inhibition of Photosystem II-Reactions in Blue-Green Algae by the Antisera to Lutein and Neoxanthin

1977 ◽  
Vol 32 (1-2) ◽  
pp. 118-124 ◽  
Author(s):  
Georg H. Schmid ◽  
Helga List ◽  
Alfons Radunz
Keyword(s):  
Electron Transport ◽  
Photosystem Ii ◽  
Green Algae ◽  
Higher Plants ◽  
Algal Species ◽  
Nostoc Muscorum ◽  
Blue Green Algae ◽  
Oscillatoria Chalybea ◽  
Electron Donation ◽  
Tetramethyl Benzidine

An antiserum to lutein agglutinates thylakoids of Nostoc muscorum and Oscillatoria chalybea. From this it follows that lutein is located in the outer surface of the thylakoid membrane of these blue-green algae. The same result is obtained for an antiserum to neoxanthin. As neoxanthin is supposed not to occur in blue-green algae it follows that in this case the antibody action should be directed towards a carotenoid with allenic structure. The antisera to lutein and neoxanthin inhibit in both investigated algal species photosynthetic electron transport on the oxygen-evolving side of photosystem II. Moreover, the inhibition sites of both antisera are identical in Nostoc muscorum and are located between the sites of electron donation of the artificial electron donors tetramethyl benzidene and diphenylcarbazide. In the case of the blue-green alga Oscillatoria chalybea the inhibition sites of both antisera differ. Whereas the inhibition site of the antiserum to neoxanthin lies again between the sites of electron donation of tetramethyl benzidine and di­phenylcarbazide, the inhibition site of the antiserum to lutein appears to be situated at least partially beyond the site of electron donation of tetramethyl benzidine. The degree of inhibition of electron transport reactions with Nostoc muscorum is for both antisera 50 - 60 per cent and is pH-dependent. The pH-optimum lies at pH 7.2 for the antiserum to neoxanthin and at 7.8 for the antiserum to lutein. In comparison to this data the same antisera inhibit electron transport in chloroplasts from higher plants only by 20%. This low degree of inhibition in higher plants is apparently due to the fact that the surfaces of the thylakoids are not accessible to antibodies within the grana. In contrast to this the thylakoid surfaces of blue-green algae are fully accessible because the thylakoids are unstacked. The thylakoids of Oscillatoria chalybea have the tendency towards aggregation. Therefore, the results concerning the accessibility of the carotenoids to antibodies are not so clear cut as with Nostoc muscorum.

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