Multi-temperature effects on Hill reaction activity of barley chloroplasts

Nolan, William G.; Smillie, Robert M.

doi:10.1016/0005-2728(76)90034-7

Cited by 91 publications

(77 citation statements)

References 19 publications

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“…These workers suggested that the observed inhibition of photosynthesis by heat stress is closely related to a perturbation of the thylakoid membranes, affecting both associated enzymes and the pigment system. These results, indicating that thylakoid membrane reactions (especially PSII activity and photophosphorylation) are some of the most heat-sensitive components in the intact leaf are in general accordance with the results of other studies in which isolated chloroplasts were subjected to heating (8,12,15,16,20). However, such comparisons must be made with some caution since heat damage of isolated chloroplasts generally occurs at considerably lower temperatures than is the case with intact leaves.…”

Section: Introductionsupporting

confidence: 88%

Photosynthetic Acclimation to Temperature in the Desert Shrub, Larrea divaricata

Armond¹,

Schreiber²,

Björkman³

1978

Plant Physiol.

210

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The response of photosynthetic electron transport and light-harvesting efficiency to high temperatures was studied in the desert shrub Larrea divaricata Cav. Plants were grown at day/night temperatures of 20/15, 32/25, or 45/33 C in rough approximation of natural seasonal temperature variations. The process of acclimation to high temperatures involves an enhancement of the stability of the interactions between the light-harvesting pigments and the photosystem reaction centers. As temperature is increased, the heat-induced dissociation of these complexes results in a decrease in the quantum yield of electron transport at limiting light intensity, followed by a loss of electron transport activity at rate-saturating light intensity. The decreased quantum yield can be attributed to a block of excitation energy transfer from chlorophyll b to chlorophyll a, and changes in the distribution of the excitation energy between photosystems II and 1. The block of excitation energy transfer is characterized by a loss of the effectiveness of 480 nm light (absorbed primarily by chlorophyll b) to drive protochemical processes, as well as fluorescence emission by chlorophyll b.Larrea divaricata Cav., a predominant desert shrub of the southwestern United States, maintains photosynthetic activity throughout the year, tolerating the great extremes of temperature which occur in warm deserts (4,13,14,17,18,23 of these leaves to high temperature, in each species was accompanied by a closely matching inhibition of the quantum yield of PSII-driven electron transport and an uncoupling of photophosphorylation in chloroplasts isolated from similarly treated leaves. Schreiber and Berry (21) showed that these inhibitory effects were coincidental with increases in Chl a fluorescence. These workers suggested that the observed inhibition of photosynthesis by heat stress is closely related to a perturbation of the thylakoid membranes, affecting both associated enzymes and the pigment system. These results, indicating that thylakoid membrane reactions (especially PSII activity and photophosphorylation) are some of the most heat-sensitive components in the intact leaf are in general accordance with the results of other studies in which isolated chloroplasts were subjected to heating (8,12,15,16,20). However, such comparisons must be made with some caution since heat damage of isolated chloroplasts generally occurs at considerably lower temperatures than is the case with intact leaves.To determine what changes in the photosynthetic apparatus of L. divaricata occur during acclimation, as well as to investigate the effect of heat damage on the light reactions, an analysis of photosynthetic electron transport and Chl fluorescence properties of chloroplasts isolated from L. divaricata plants grown under different temperature regimes was performed. It will be demonstrated that a substantial part of the heat-induced damage to the photosynthetic apparatus is at the pigment system level, and that the process of acclimation results in an increased st...

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Section: Introductionsupporting

confidence: 88%

Photosynthetic Acclimation to Temperature in the Desert Shrub, Larrea divaricata

Armond¹,

Schreiber²,

Björkman³

1978

Plant Physiol.

210

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“…The chosen upper limit, Jmax, placed on electron transport of 467btEq (gChl)-i s-1 (=l,680gEq (mgChl)-lh -1) at 25C, derives from the measurements of Nolan and Smillie (1976) on chloroplasts of Hordeum vulgate (see Fig. 2).…”

Section: Electron Transport and The Production And Consumption Of Nadphmentioning

confidence: 99%

“…The data of Nolan and Smillie (1976) (Fig. 2) were used to determine the coefficient 483 and parameters E, S and H for use in the following expression…”

Section: Temperaturementioning

confidence: 99%

A biochemical model of photosynthetic CO2 assimilation in leaves of C3 species

Farquhar

Caemmerer

Berry

1980

Planta

7,663

6,691

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Abstract.Various aspects of the biochemistry of photosynthetic carbon assimilation in C3 plants are integrated into a form compatible with studies of gas exchange in leaves. These aspects include the kinetic properties of ribulose bisphosphate carboxylaseoxygenase; the requirements of the photosynthetic carbon reduction and photorespiratory carbon oxidation cycles for reduced pyridine nucleotides; the dependence of electron transport on photon flux and the presence of a temperature dependent upper limit to electron transport. The measurements of gas exchange with which the model outputs may be compared include those of the temperature and partial pressure of CO2(p(CO2) ) dependencies of quantum yield, the variation of compensation point with temperature and partial pressure of O2(p(O2)), the dependence of net CO 2 assimilation rate on p(CO2) and irradiance, and the influence of p(CO2) and irradiance on the temperature dependence of assimilation rate.

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“…Thus, a relatively low viscosity may be expected for the thylakoid membrane at room temperature (2). However, the membrane fluidity can be changed by varying the temperature of the chloroplast suspension and a great deal of evidence has accumulated suggesting effects of temperature on function ofchloroplasts, including electron transport, fluorescence changes, and other related reactions (6,9,13,14,16,19,20,22,29,30,33,34). The viscosity of membranes can also be changed by introducing other membrane components such as sterols and in particular the effects of cholesterol on artificial lipid membranes have been well characterized and reviewed by several authors (7,23 thylakoid lipid phase on the functioning of various photosynthetic processes such as electron transport, ionic conductivity of the membrane, and cation-induced Chl fluorescence changes.…”

mentioning

confidence: 99%

Relationship between Thylakoid Membrane Fluidity and the Functioning of Pea Chloroplasts

Yamamoto¹,

Ford²,

Barber³

1981

Plant Physiol.

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Cholesteryl hemisuccinate has been incorporated into pea chloroplast thylakoids to investigate the relationship between fluidity and functioning of this membrane system. Levels of sterol which increased the apparent viscosity of the membrane, estimated by fluorescence polarization measurements using the lppboilic probe, 1,6-diphenyl-1,3,5 hexatriene, affected several photosynthetic processes. A decrease in fluidity was accompanied by an inhibition of dark limiting steps associated with electron transfer between photosystems two and one (PSII and PSI) as observed by the oxidation of the primary acceptor of PSII and by electron flow to ferricyanide. Also, treatment with cholesteryl hemisuccinate inhibited the saltinduced rise in chlorophyli fluorescence and changed the ionic conductivity of the membrane as judged by measurements of the decay of the lightinduced proton gradient. The results are discussed in terms of the effect of fluidity changes on the lateral dfffusion of plastoquinone and chlorophyli protein complexes in the lipid matrix of the membrane.There is increasing evidence that the fluidity of the chloroplast thylakoid membrane may play an important role in controlling the light reactions of photosynthesis (4, 24). The fluidity of biological membranes is determined mainly by the length and the degree of saturation of alkyl chains in fatty acids of the constituent lipids. Thylakoid membranes of higher plants contain galactolipids with highly unsaturated fatty acids and a small portion of phospho-and sulfolipids (1,5,15). Thus, a relatively low viscosity may be expected for the thylakoid membrane at room temperature (2). However, the membrane fluidity can be changed by varying the temperature of the chloroplast suspension and a great deal of evidence has accumulated suggesting effects of temperature on function ofchloroplasts, including electron transport, fluorescence changes, and other related reactions (6,9,13,14,16,19,20,22,29,30,33,34 thylakoid lipid phase on the functioning of various photosynthetic processes such as electron transport, ionic conductivity of the membrane, and cation-induced Chl fluorescence changes. Although this sterol occurs only at low levels in higher plants its effect on the physical properties of biological membranes in general is well documented. Thus, we have simply used this compound, added as the hemisuccinate, in an attempt to artificialy manipulate the fluidity of the thylakoid membrane. MATERIALS AND METHODSPea chloroplasts were prepared according to Nakatani and Barber (21), and then osmotically disrupted, washed once, and suspended in 0.33 M sorbitol and 1 mm Tris-HCl solution (pH 7.5). Cholesteryl hemisuccinate was added to thylakoid membranes by the method of Shinitzky et al. (28); 3.5% (w/w) of polyvinyl pyrrolidone (PVP, Mr 40,000, Sigma) was incubated with 25 mm Tris-HCl buffer (pH 7.5) for at least 30 min and cholesteryl hemisuccinate (Tris-salt), dissolved in a small amount of tetrahydrofuran, was added to give the required concentration. The cholestery...

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Multi-temperature effects on Hill reaction activity of barley chloroplasts

Cited by 91 publications

References 19 publications

Photosynthetic Acclimation to Temperature in the Desert Shrub, Larrea divaricata

Photosynthetic Acclimation to Temperature in the Desert Shrub, Larrea divaricata

A biochemical model of photosynthetic CO2 assimilation in leaves of C3 species

Relationship between Thylakoid Membrane Fluidity and the Functioning of Pea Chloroplasts

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