Sulfur starvation in Lemna leads to degradation of ribulose-bisphosphate carboxylase without plant death.

Ferreira, Ricardo Manuel Boavida; Teixeira, A.

doi:10.1016/s0021-9258(18)42512-4

Cited by 78 publications

(5 citation statements)

References 22 publications

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“…Figure 5a shows a Western blot analysis of Rubisco in C. reinhardtii suspended in the absence of S (0 M) or in the presence of limited amount of S (50 M). The results show a precipitous decline in the amount of this protein as a function of time in S deprivation (Ferreira & Teixeira 1992;Giordano et al 2000;Zhang et al 2002). Only ca.…”

Section: (C) Protein Substrate Catabolism Under Sulphurdeprivation Conditions In C Reinhardtiimentioning

confidence: 86%

Probing green algal hydrogen production

Zhang

Melis

2002

Phil. Trans. R. Soc. Lond. B

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The recently developed two-stage photosynthesis and H(2)-production protocol with green algae is further investigated in this work. The method employs S deprivation as a tool for the metabolic regulation of photosynthesis. In the presence of S, green algae perform normal photosynthesis, carbohydrate accumulation and oxygen production. In the absence of S, normal photosynthesis stops and the algae slip into the H(2)-production mode. For the first time, to our knowledge, significant amounts of H(2) gas were generated, essentially from sunlight and water. Rates of H(2) production could be sustained continuously for ca. 80 h in the light, but gradually declined thereafter. This work examines biochemical and physiological aspects of this process in the absence or presence of limiting amounts of S nutrients. Moreover, the effects of salinity and of uncouplers of phosphorylation are investigated. It is shown that limiting levels of S can sustain intermediate levels of oxygenic photosynthesis, in essence raising the prospect of a calibration of the rate of photosynthesis by the S content in the growth medium of the algae. It is concluded that careful titration of the supply of S nutrients in the green alga medium might permit the development of a continuous H(2)-production process.

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Section: (C) Protein Substrate Catabolism Under Sulphurdeprivation Conditions In C Reinhardtiimentioning

confidence: 86%

Probing green algal hydrogen production

Zhang

Melis

2002

Phil. Trans. R. Soc. Lond. B

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“…were obtained in a local market. Duckweed (Lemna minor L.) was grown as described before (Ferreira and Teixeira, 1992).…”

Section: Introductionmentioning

confidence: 99%

“…Ribulose bisphosphate carboxylase was purified from L. minor by FPLC anion-exchange chromatography on a Mono Q column followed by gel filtration on a Superose 12 column as described by Ferreira and Teixeira (1992).…”

Section: Introductionmentioning

confidence: 99%

Calcium- and Magnesium-Dependent Aggregation of Legume Seed Storage Proteins

Ferreira

Franco

Teixeira

1999

J. Agric. Food Chem.

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The solubility characteristics and sedimentation behavior of total or individual globulins from legume seeds [Lupinus albus L., Pisum sativum L., and Glycine max (L.) Merr.] were investigated. The typical insolubility of globulins detected during their extraction seems to be due to the presence of a low molecular weight factor(s) in the seed extract. The solubility of the purified globulins decreases with increasing concentrations of calcium and/or magnesium, but not of other cations, showing minimum values at concentrations that vary with the particular globulin considered. Ultracentrifugation analyses revealed that the Ca(2+)- and/or Mg(2+)-induced insolubilization of the globulins involves the formation of high-order aggregates of molecules of the same or of different globulins. These macromolecular structures are dissociated under conditions of high ionic strength, suggesting the involvement of electrostatic interactions in the aggregation process. The degree of association relies heavily on the amount of Ca(2+) and/or Mg(2+) available, on the presence of chelating agents for these divalent cations, and on the ionic strength of the surrounding medium. The possible physiological significance of the findings is discussed.

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“…], and broad bean (Vicia faba L.) were obtained in a local market. Duckweed (Lemna minor L.) was grown as described before (Ferreira and Teixeira, 1992).…”

Section: Methodsmentioning

confidence: 99%

“…Protein concentration was measured according to a modification of the Lowry method (Bensadoun and Weinstein, 1976). Lemna ribulose bisphosphate carboxylase was purified by anion exchange chromatography on the FPLC (Pharmacia/LKB) Mono Q column and by gel filtration on the FPLC Superose 12 column as previously described (Ferreira and Teixeira, 1992). Immunoglobulins G were purified from goat serum by affinity chromatography on the protein G-Superose column of the FPLC (Ferreira et al, 1996).…”

Section: Methodsmentioning

confidence: 99%

Utilization of an Improved Methodology To Isolate Lupinus albus Conglutins in the Study of Their Sedimentation Coefficients

Franco

Ferreira

Teixeira

1997

J. Agric. Food Chem.

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Methods utilized frequently for the extraction of globulins from legume seeds lead to a considerable loss of these proteins in the albumin fraction due to a partial solubilization of globulins in the albumin extraction medium. The standard procedure to isolate legume seed globulins was modified by (i) including calcium and magnesium in the albumin extraction solution, which completely solubilizes the albumins free of contaminating globulins, and (ii) adding EDTA and EGTA to the globulin extraction solution, which efficiently extract the globulins. Using this modified methodology, Lupinus albus globulins were isolated and subsequently purified, and the main individual globulins, namely α-, β-, and γ-conglutins, were characterized. α- and β-conglutins have been routinely considered as the 11S (or legumin-like) and 7S (or vicilin-like), respectively, protein components of L. albus seeds. Using the total globulin fraction or the purified conglutins on isopycnic sucrose or glycerol density gradient centrifugation performed under low or high ionic strength and on gel filtration techniques, it is proposed that β-conglutin (with a sedimentation coefficient of approximately 11 S) is considerably heavier than α-conglutin (with a sedimentation coefficient of approximately 7 S). Keywords: Extraction; globulins; legume seeds; Lupinus albus; sedimentation coefficients

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Sulfur starvation in Lemna leads to degradation of ribulose-bisphosphate carboxylase without plant death.

Cited by 78 publications

References 22 publications

Probing green algal hydrogen production

Probing green algal hydrogen production

Calcium- and Magnesium-Dependent Aggregation of Legume Seed Storage Proteins

Utilization of an Improved Methodology To Isolate Lupinus albus Conglutins in the Study of Their Sedimentation Coefficients

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