摘要:

SUMMARYThe influence of temperature, CO2availability, light intensity, and colour on growth ofAnacystisat high (70–120 W·m−2) light intensities was investigated. In the first days rapid formation of cells with a high nitrogen content was found. During this period the nitrogen content of the cells was about 10%. When the supply of bound nitrogen was exhausted, the over‐all photosynthetic mechanism switched to production of nitrogen deficient products, probably carbohydrates. Only in the first period growth could be followed by measuring optical parameters, and a production of 0.5–1 g·l−1dry weight per day could be obtained in single batch as well as in continuo

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1977.tb01116.x

年代:1977

数据来源: WILEY

摘要:

SUMMARYThe two pigment systems, with optimum activity at 675 nm and 750 nm, that are responsible for light dependent oxygen uptake byAnacystis nidulansremain active in the presence of DCMU. The activity of the 750 nm system is increased at the beginning of the phase of exponential growth when L‐glutamate has been added to the growth medium. We presume that variations in growth conditions may induce the formation of endogenous reductants that cause increased oxygen uptake. Experiments with added reductants showed that L‐ascorbate, DCPIPH2and TMPD are readily photooxidized in the intact cell by the 750 nm sys

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1977.tb01117.x

年代:1977

数据来源: WILEY

摘要:

SUMMARYThe photoconvertible chlorophyll‐protein complex Cp668 → Cp743 could be observed in situ after a freeze‐thaw treatment inChenopodiumandAmaranthus. The concentration of the complex was highest in sections of the upper part of the stem. Capacity for photoconversion developed gradually after thawing. WithChenopodiumthe yield of Cp668 → Cp743 depended to a large extent on growing conditions of the plant, withAmaranthusmuch less variability was found. In preparations fromAmaranthusefficient energy transfer between pigments attached to a common protein carrier could be demonstrated. The initial quantum efficiency of Cp668 → Cp743 photoconversion was similar to that of protochlorophyll‐chlorophyll photoconversion. A possible relation between various photoprocesses in the measured plants i

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1977.tb01118.x

年代:1977

数据来源: WILEY

摘要:

SUMMARYThe marine algaChlamydomonasspec. contains a very high concentration of chlorophyllb. Electron micrographs of freeze‐fracture preparations show that membrane particles occur in two sizes and in two different population densities. Computer analysis of a low temperature absorption spectrum shows a high amount of chlorophyllbbut only moderate amounts of chlorophylla‐640 and of chlorophylla

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1977.tb01119.x

年代:1977

数据来源: WILEY

摘要:

SUMMARYPreparations of isolated chloroplasts show a reduction of photophosphorylation activity due to ageing even when stored in the dark at 0–4°C in a stabilizing medium. The rate of activity loss depends strongly upon the type of photophosphorylation. With non‐cyclic photophosphorylation (ferricyanide or NADP‐ferredoxin) reduction of activity is rapid immediately after isolation of chloroplasts, whereas it decreases to much slower rates after 3–4 hours. In the presence of PMS, which under our reaction conditions serves as electron acceptor for PS‐2 and electron donor for PS‐1, photophosphorylation activity is hardly affected by the increasing age of chloroplasts. However, upon addition of low concentrations of DCMU, reduction of this phosphorylation activity due to ageing shows the same kinetics as non‐cyclic photophosphorylation. Photophosphorylation of PS‐1 (reduced DCPIP‐MVDCMU) is hardly affected by the agei

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1977.tb01120.x

年代:1977

数据来源: WILEY

摘要:

SUMMARYAction spectra of PS‐1 photophosphorylation show absorption bands or shoulders with peak locations around 640, 647–650, 660, 672–674, 680, 690, 701–703, 710–712 and 721 nm. Phosphorylation activity is reduced around 665–667 and 676 nm suggesting decreased absorption bands of pigments involved in the light absorption proc

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1977.tb01121.x

年代:1977

数据来源: WILEY

摘要:

SUMMARYTreatment ofPhaseolus vulgarischloroplast fragments with 8 or 4 mM digitonin as well as 8 or 4 mM sodium dodecyl sulfate results in a proportionally higher solubilization of the chlorophylla685 complex and a lower one of chlorophyllbas compared to the extractability of the remaining chlorophyllaforms. The results are discussed with respect to previous data suggesting the occurrence of a chlorophyllb‐chlorophylla685‐protein complex. It may be that both pigment forms are bound to different polypeptides of this comp

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1977.tb01122.x

年代:1977

数据来源: WILEY

摘要:

SUMMARYA DNA‐DNA hybridization membrane filter method suitable for blue‐green algal DNA was developed. One of the main obstacles, the high amount of aspecific binding of the blue‐green algal DNA to filters, could be resolved by means of an additional purification step involving isopycnic centrifugation of the thoroughly purified DNA. Application on DNA of several strains of blue‐green algae indicates that this method is useful for taxonomic p

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1977.tb01123.x

年代:1977

数据来源: WILEY

摘要:

SUMMARYCross‐sections were made of developing gibbous and flat fronds ofLemna gibbaG3 which were emerging from the reproductive pocket of the mother plant. In the gibbous fronds the cells of the developing air chamber walls and peripheral walls were in a more active stage of division than in the flat fronds. Consequently, it was demonstrated that gibbosity is initiated in a young developing frond mainly as a result of enhanced cell division and the subsequent increase in the number of cell

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1977.tb01124.x

年代:1977

数据来源: WILEY

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1977.tb01125.x

年代:1977

数据来源: WILEY