Zechmann, Bernd

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  • Zechmann, Bernd (3)
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Author's Bibliography

Mechanisms of detoxification of high copper concentrations by the microalga Chlorella sorokiniana

Vojvodić, Snežana; Stanić, Marina; Zechmann, Bernd; Dučić, Tanja; Žižić, Milan; Dimitrijević, Milena; Danilović Luković, Jelena; Milenković, Milica R.; Pittman, Jon K.; Spasojević, Ivan

(Portland Press, 2020)

TY  - JOUR
AU  - Vojvodić, Snežana
AU  - Stanić, Marina
AU  - Zechmann, Bernd
AU  - Dučić, Tanja
AU  - Žižić, Milan
AU  - Dimitrijević, Milena
AU  - Danilović Luković, Jelena
AU  - Milenković, Milica R.
AU  - Pittman, Jon K.
AU  - Spasojević, Ivan
PY  - 2020
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/4263
AB  - Microalgae have evolved mechanisms to respond to changes in copper ion availability, which are very important for normal cellular function, to tolerate metal pollution of aquatic ecosystems, and for modulation of copper bioavailability and toxicity to other organisms. Knowledge and application of these mechanisms will benefit the use of microalgae in wastewater processing and biomass production, and the use of copper compounds in the suppression of harmful algal blooms. Here, using electron microscopy, synchrotron radiation-based Fourier transform infrared spectroscopy, electron paramagnetic resonance spectroscopy, and X-ray absorption fine structure spectroscopy, we show that the microalga Chlorella sorokiniana responds promptly to Cu2+ at high non-toxic concentration, by mucilage release, alterations in the architecture of the outer cell wall layer and lipid structures, and polyphosphate accumulation within mucilage matrix. The main route of copper detoxification is by Cu2+ coordination to polyphosphates in penta-coordinated geometry. The sequestrated Cu2+ was accessible and could be released by extracellular chelating agents. Finally, the reduction in Cu2+ to Cu1+ appears also to take place. These findings reveal the biochemical basis of the capacity of microalgae to adapt to high external copper concentrations and to serve as both, sinks and pools of environmental copper.
PB  - Portland Press
T2  - The Biochemical Journal
T1  - Mechanisms of detoxification of high copper concentrations by the microalga Chlorella sorokiniana
VL  - 477
IS  - 19
SP  - 3729
EP  - 3741
DO  - 10.1042/BCJ20200600
ER  - 
@article{
author = "Vojvodić, Snežana and Stanić, Marina and Zechmann, Bernd and Dučić, Tanja and Žižić, Milan and Dimitrijević, Milena and Danilović Luković, Jelena and Milenković, Milica R. and Pittman, Jon K. and Spasojević, Ivan",
year = "2020",
abstract = "Microalgae have evolved mechanisms to respond to changes in copper ion availability, which are very important for normal cellular function, to tolerate metal pollution of aquatic ecosystems, and for modulation of copper bioavailability and toxicity to other organisms. Knowledge and application of these mechanisms will benefit the use of microalgae in wastewater processing and biomass production, and the use of copper compounds in the suppression of harmful algal blooms. Here, using electron microscopy, synchrotron radiation-based Fourier transform infrared spectroscopy, electron paramagnetic resonance spectroscopy, and X-ray absorption fine structure spectroscopy, we show that the microalga Chlorella sorokiniana responds promptly to Cu2+ at high non-toxic concentration, by mucilage release, alterations in the architecture of the outer cell wall layer and lipid structures, and polyphosphate accumulation within mucilage matrix. The main route of copper detoxification is by Cu2+ coordination to polyphosphates in penta-coordinated geometry. The sequestrated Cu2+ was accessible and could be released by extracellular chelating agents. Finally, the reduction in Cu2+ to Cu1+ appears also to take place. These findings reveal the biochemical basis of the capacity of microalgae to adapt to high external copper concentrations and to serve as both, sinks and pools of environmental copper.",
publisher = "Portland Press",
journal = "The Biochemical Journal",
title = "Mechanisms of detoxification of high copper concentrations by the microalga Chlorella sorokiniana",
volume = "477",
number = "19",
pages = "3729-3741",
doi = "10.1042/BCJ20200600"
}
Vojvodić, S., Stanić, M., Zechmann, B., Dučić, T., Žižić, M., Dimitrijević, M., Danilović Luković, J., Milenković, M. R., Pittman, J. K.,& Spasojević, I.. (2020). Mechanisms of detoxification of high copper concentrations by the microalga Chlorella sorokiniana. in The Biochemical Journal
Portland Press., 477(19), 3729-3741.
https://doi.org/10.1042/BCJ20200600
Vojvodić S, Stanić M, Zechmann B, Dučić T, Žižić M, Dimitrijević M, Danilović Luković J, Milenković MR, Pittman JK, Spasojević I. Mechanisms of detoxification of high copper concentrations by the microalga Chlorella sorokiniana. in The Biochemical Journal. 2020;477(19):3729-3741.
doi:10.1042/BCJ20200600 .
Vojvodić, Snežana, Stanić, Marina, Zechmann, Bernd, Dučić, Tanja, Žižić, Milan, Dimitrijević, Milena, Danilović Luković, Jelena, Milenković, Milica R., Pittman, Jon K., Spasojević, Ivan, "Mechanisms of detoxification of high copper concentrations by the microalga Chlorella sorokiniana" in The Biochemical Journal, 477, no. 19 (2020):3729-3741,
https://doi.org/10.1042/BCJ20200600 . .
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The effects of ionizing radiation on the structure and antioxidative and metal-binding capacity of the cell wall of microalga Chlorella sorokiniana

Danilović Luković, Jelena; Zechmann, Bernd; Jevtović, Mima; Bogdanović Pristov, Jelena; Stanić, Marina; Marco Lizzul, Alessandro; Pittman, Jon K.; Spasojević, Ivan

(Elsevier, 2020)

TY  - JOUR
AU  - Danilović Luković, Jelena
AU  - Zechmann, Bernd
AU  - Jevtović, Mima
AU  - Bogdanović Pristov, Jelena
AU  - Stanić, Marina
AU  - Marco Lizzul, Alessandro
AU  - Pittman, Jon K.
AU  - Spasojević, Ivan
PY  - 2020
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/4241
AB  - The impact of ionizing radiation on microorganisms such as microalgae is a topic of increasing importance for understanding the dynamics of aquatic ecosystems in response to environmental radiation, and for the development of efficient approaches for bioremediation of mining and nuclear power plants wastewaters. Currently, nothing is known about the effects of ionizing radiation on the microalgal cell wall, which represents the first line of defence against chemical and physical environmental stresses. Using various microscopy, spectroscopy and biochemical techniques we show that the unicellular alga Chlorella sorokiniana elicits a fast response to ionizing radiation. Within one day after irradiation with doses of 1–5 Gy, the fibrilar layer of the cell wall became thicker, the fraction of uronic acids was higher, and the capacity to remove the main reactive product of water radiolysis increased. In addition, the isolated cell wall fraction showed significant binding capacity for Cu2+, Mn2+, and Cr3+. The irradiation further increased the binding capacity for Cu2+, which appears to be mainly bound to glucosamine moieties within a chitosan-like polymer in the outer rigid layer of the wall. These results imply that the cell wall represents a dynamic structure that is involved in the protective response of microalgae to ionizing radiation. It appears that microalgae may exhibit a significant control of metal mobility in aquatic ecosystems via biosorption by the cell wall matrix.
PB  - Elsevier
T2  - Chemosphere
T1  - The effects of ionizing radiation on the structure and antioxidative and metal-binding capacity of the cell wall of microalga Chlorella sorokiniana
VL  - 260
SP  - 127553
DO  - 10.1016/j.chemosphere.2020.127553
ER  - 
@article{
author = "Danilović Luković, Jelena and Zechmann, Bernd and Jevtović, Mima and Bogdanović Pristov, Jelena and Stanić, Marina and Marco Lizzul, Alessandro and Pittman, Jon K. and Spasojević, Ivan",
year = "2020",
abstract = "The impact of ionizing radiation on microorganisms such as microalgae is a topic of increasing importance for understanding the dynamics of aquatic ecosystems in response to environmental radiation, and for the development of efficient approaches for bioremediation of mining and nuclear power plants wastewaters. Currently, nothing is known about the effects of ionizing radiation on the microalgal cell wall, which represents the first line of defence against chemical and physical environmental stresses. Using various microscopy, spectroscopy and biochemical techniques we show that the unicellular alga Chlorella sorokiniana elicits a fast response to ionizing radiation. Within one day after irradiation with doses of 1–5 Gy, the fibrilar layer of the cell wall became thicker, the fraction of uronic acids was higher, and the capacity to remove the main reactive product of water radiolysis increased. In addition, the isolated cell wall fraction showed significant binding capacity for Cu2+, Mn2+, and Cr3+. The irradiation further increased the binding capacity for Cu2+, which appears to be mainly bound to glucosamine moieties within a chitosan-like polymer in the outer rigid layer of the wall. These results imply that the cell wall represents a dynamic structure that is involved in the protective response of microalgae to ionizing radiation. It appears that microalgae may exhibit a significant control of metal mobility in aquatic ecosystems via biosorption by the cell wall matrix.",
publisher = "Elsevier",
journal = "Chemosphere",
title = "The effects of ionizing radiation on the structure and antioxidative and metal-binding capacity of the cell wall of microalga Chlorella sorokiniana",
volume = "260",
pages = "127553",
doi = "10.1016/j.chemosphere.2020.127553"
}
Danilović Luković, J., Zechmann, B., Jevtović, M., Bogdanović Pristov, J., Stanić, M., Marco Lizzul, A., Pittman, J. K.,& Spasojević, I.. (2020). The effects of ionizing radiation on the structure and antioxidative and metal-binding capacity of the cell wall of microalga Chlorella sorokiniana. in Chemosphere
Elsevier., 260, 127553.
https://doi.org/10.1016/j.chemosphere.2020.127553
Danilović Luković J, Zechmann B, Jevtović M, Bogdanović Pristov J, Stanić M, Marco Lizzul A, Pittman JK, Spasojević I. The effects of ionizing radiation on the structure and antioxidative and metal-binding capacity of the cell wall of microalga Chlorella sorokiniana. in Chemosphere. 2020;260:127553.
doi:10.1016/j.chemosphere.2020.127553 .
Danilović Luković, Jelena, Zechmann, Bernd, Jevtović, Mima, Bogdanović Pristov, Jelena, Stanić, Marina, Marco Lizzul, Alessandro, Pittman, Jon K., Spasojević, Ivan, "The effects of ionizing radiation on the structure and antioxidative and metal-binding capacity of the cell wall of microalga Chlorella sorokiniana" in Chemosphere, 260 (2020):127553,
https://doi.org/10.1016/j.chemosphere.2020.127553 . .
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1

Carbon allocation from source to sink leaf tissue in relation to flavonoid biosynthesis in variegated Pelargonium zonale under UV-B radiation and high PAR intensity

Vidović, Marija; Morina, Filis; Milic, Sonja; Albert, Andreas; Zechmann, Bernd; Tosti, Tomislav; Winkler, Jana Barbro; Veljović-Jovanović, Sonja

(Elsevier France-Editions Scientifiques Medicales Elsevier, Paris, 2015)

TY  - JOUR
AU  - Vidović, Marija
AU  - Morina, Filis
AU  - Milic, Sonja
AU  - Albert, Andreas
AU  - Zechmann, Bernd
AU  - Tosti, Tomislav
AU  - Winkler, Jana Barbro
AU  - Veljović-Jovanović, Sonja
PY  - 2015
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/1727
AB  - We studied the specific effects of high photosynthetically active radiation (PAR, 400-700 nm) and ecologically relevant UV-B radiation (0.90 W m(-2)) on antioxidative and phenolic metabolism by exploiting the green-white leaf variegation of Pelargonium zonale plants. This is a suitable model system for examining "source-sink" interactions within the same leaf. High PAR intensity (1350 mu mol m(-2) s(-1)) and UV-B radiation induced different responses in green and white leaf sectors. High PAR intensity had a greater influence on green tissue, triggering the accumulation of phenylpropanoids and flavonoids with strong antioxidative function. Induced phenolics, together with ascorbate, ascorbate peroxidase (APX, EC 1.11.1.11) and catalase (CAT, EC 1.11.1.6) provided efficient defense against potential oxidative pressure. UV-B-induced up-regulation of non-phenolic H2O2 scavengers in green leaf sectors was greater than high PAR-induced changes, indicating a UV-B role in antioxidative defense under light excess; on the contrary, minimal effects were observed in white tissue. However, UV-B radiation had greater influence on phenolics in white leaf sections compared to green ones, inducing accumulation of phenolic glycosides whose function was UV-B screening rather than antioxidative. By stimulation of starch and sucrose breakdown and carbon allocation in the form of soluble sugars from "source" (green) tissue to "sink" (white) tissue, UV-B radiation compensated the absence of photosynthetic activity and phenylpropanoid and flavonoid biosynthesis in white sectors. (C) 2015 Elsevier Masson SAS. All rights reserved.
PB  - Elsevier France-Editions Scientifiques Medicales Elsevier, Paris
T2  - Plant Physiology and Biochemistry
T1  - Carbon allocation from source to sink leaf tissue in relation to flavonoid biosynthesis in variegated Pelargonium zonale under UV-B radiation and high PAR intensity
VL  - 93
SP  - 44
EP  - 55
DO  - 10.1016/j.plaphy.2015.01.008
UR  - Kon_2873
ER  - 
@article{
author = "Vidović, Marija and Morina, Filis and Milic, Sonja and Albert, Andreas and Zechmann, Bernd and Tosti, Tomislav and Winkler, Jana Barbro and Veljović-Jovanović, Sonja",
year = "2015",
abstract = "We studied the specific effects of high photosynthetically active radiation (PAR, 400-700 nm) and ecologically relevant UV-B radiation (0.90 W m(-2)) on antioxidative and phenolic metabolism by exploiting the green-white leaf variegation of Pelargonium zonale plants. This is a suitable model system for examining "source-sink" interactions within the same leaf. High PAR intensity (1350 mu mol m(-2) s(-1)) and UV-B radiation induced different responses in green and white leaf sectors. High PAR intensity had a greater influence on green tissue, triggering the accumulation of phenylpropanoids and flavonoids with strong antioxidative function. Induced phenolics, together with ascorbate, ascorbate peroxidase (APX, EC 1.11.1.11) and catalase (CAT, EC 1.11.1.6) provided efficient defense against potential oxidative pressure. UV-B-induced up-regulation of non-phenolic H2O2 scavengers in green leaf sectors was greater than high PAR-induced changes, indicating a UV-B role in antioxidative defense under light excess; on the contrary, minimal effects were observed in white tissue. However, UV-B radiation had greater influence on phenolics in white leaf sections compared to green ones, inducing accumulation of phenolic glycosides whose function was UV-B screening rather than antioxidative. By stimulation of starch and sucrose breakdown and carbon allocation in the form of soluble sugars from "source" (green) tissue to "sink" (white) tissue, UV-B radiation compensated the absence of photosynthetic activity and phenylpropanoid and flavonoid biosynthesis in white sectors. (C) 2015 Elsevier Masson SAS. All rights reserved.",
publisher = "Elsevier France-Editions Scientifiques Medicales Elsevier, Paris",
journal = "Plant Physiology and Biochemistry",
title = "Carbon allocation from source to sink leaf tissue in relation to flavonoid biosynthesis in variegated Pelargonium zonale under UV-B radiation and high PAR intensity",
volume = "93",
pages = "44-55",
doi = "10.1016/j.plaphy.2015.01.008",
url = "Kon_2873"
}
Vidović, M., Morina, F., Milic, S., Albert, A., Zechmann, B., Tosti, T., Winkler, J. B.,& Veljović-Jovanović, S.. (2015). Carbon allocation from source to sink leaf tissue in relation to flavonoid biosynthesis in variegated Pelargonium zonale under UV-B radiation and high PAR intensity. in Plant Physiology and Biochemistry
Elsevier France-Editions Scientifiques Medicales Elsevier, Paris., 93, 44-55.
https://doi.org/10.1016/j.plaphy.2015.01.008
Kon_2873
Vidović M, Morina F, Milic S, Albert A, Zechmann B, Tosti T, Winkler JB, Veljović-Jovanović S. Carbon allocation from source to sink leaf tissue in relation to flavonoid biosynthesis in variegated Pelargonium zonale under UV-B radiation and high PAR intensity. in Plant Physiology and Biochemistry. 2015;93:44-55.
doi:10.1016/j.plaphy.2015.01.008
Kon_2873 .
Vidović, Marija, Morina, Filis, Milic, Sonja, Albert, Andreas, Zechmann, Bernd, Tosti, Tomislav, Winkler, Jana Barbro, Veljović-Jovanović, Sonja, "Carbon allocation from source to sink leaf tissue in relation to flavonoid biosynthesis in variegated Pelargonium zonale under UV-B radiation and high PAR intensity" in Plant Physiology and Biochemistry, 93 (2015):44-55,
https://doi.org/10.1016/j.plaphy.2015.01.008 .,
Kon_2873 .
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