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41.
Consequences of iron deficiency on photosynthetic and respiratory electron transport in blue-green algae 总被引:3,自引:0,他引:3
Gerhard Sandmann 《Photosynthesis research》1985,6(3):261-271
Growth of Aphanocapsa in low iron media resulted in a decrease of the endogenous iron pool. Below a critical concentration photosynthetic electron transfer was specifically depressed. This was caused by a strong inhibition of the synthesis of cytochromes b-559 of PSII, cytochromes b-563, f-557, and the Rieske Fe-S center of the cytochrome complex and especially the Fe-S centers of PSI. The influence of iron limitation on respiration and chlorphyll formation was negligible.Paper presented at the FESPP meeting (Strasbourg, 1984) 相似文献
42.
43.
Phytoplankton production and respiration in the Blue Nile and White Nile at Khartoum were measured during the period November 1969–January 1971 using the light and dark bottle technique. Maximum rates of production coincided with periods of maximum phytoplankton densities. In the Blue Nile gross production varied between 0.00 gCm–3d–1 during the flood season and 2.19 gCm–3d–1 (0.49 mgO2l–1h–1) during November 1969. In the White Nile the range was from 0.41 gCm–3d–1 (0.09 MgO2l–1h–1) in May to 3.74 gCm–3d–1 (0.83 MgO2l–1h–1) in November. The maximum rates of respiration in the Blue Nile and White Nile were 0.10 and 0.63 MgO2l–1h–1 respectively. The ratios net:gross production were generally higher in the White Nile than in the Blue Nile. 相似文献
44.
45.
Managing wild crops of Gracilaria in central Chile 总被引:3,自引:3,他引:0
46.
47.
Antitumor evaluation of marine algae in Argentina 总被引:3,自引:3,他引:0
48.
Summary Cells ofScherffelia dubia regenerate flagella with a complete scale covering after experimental flagellar amputation. Flagellar regeneration was used to study Golgi apparatus (GA) activity during flagellar scale production. By comparing the number of scales present on mature flagella with the flagellar regeneration kinetics, it is calculated that each cell produces ca. 260 scales per minute during flagellar regeneration. Flagellar scales are assembled exclusively in the GA and abstricted from the rims of thetrans-most GA cisternae into vesicles. Exocytosis of scales occurs at the base of the anterior flagellar groove. The central portion of thetrans-most cisterna, containing no scales, detaches from the stack of cisternae and develops a coat to become a coated polygonal vesicle. Scale biogenesis involves continuous turnover of GA cisternae, and scale production rates indicate maturation of four cisternae per minute from each of the cells two dictyosomes. A possible model of membrane flow routes during flagellar regeneration, which involves a membrane recycling loop via the coated polygonal vesicles, is presented. 相似文献
49.
The amino acid sequences of cytochrome c553 from the eukaryotic red alga Porphyridium cruentum and from the prokaryotic cyanobacterium Aphanizomenon flos-aquae have been determined from the tryptic and cyanogen bromide peptides. The results indicate that a charged region of these proteins has evolved with special rapidity to accomodate a rapid evolution of a binding site in the P700 electron acceptor complex. 相似文献
50.
Evidence is presented here that axenic cultures of Nostoc spp., Aphanocapsa (PCC 6308), and Aphanocapsa (PCC 6714) but not Anacystis nidulans R-2 (PCC 7942) produce N2O and ammonia when grown on nitrite. The data suggest that the cyanobacteria produce N2O by nitrite reduction to ammonia.Nonstandard abbreviations DCMU
3-(3,4-dichlorophenyl)-1,1-dimethyl urea
- NIR
nitrite reductase 相似文献