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1.
Environ Sci Pollut Res Int ; 30(25): 67250-67262, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37103714

RESUMO

Copper is an essential micronutrient, but at supraoptimal concentrations it is also highly toxic, inducing oxidative stress and disrupting photosynthesis. The aim of the present study was to analyze selected protective mechanisms in strains of Chlamydomonas reinhardtii adapted and not adapted for growth in the presence of elevated copper concentrations. Two algal lines (tolerant and non-tolerant to high Cu2+ concentrations) were used in experiments to study photosynthetic pigment content, peroxidase activity, and non-photochemical quenching. The content of prenyllipids was studied in four different algal lines (two of the same as above and two new ones). The copper-adapted strains contained about 2.6 times more α-tocopherol and plastoquinol and about 1.7 times more total plastoquinone than non-tolerant strains. Exposure to excess copper led to oxidation of the plastoquinone pool in non-tolerant strains, whereas this effect was less pronounced or did not occur in copper-tolerant strains. Peroxidase activity was approximately 1.75 times higher in the tolerant strain than in the non-tolerant one. The increase in peroxidase activity in the tolerant strain was less pronounced when the algae were grown in dim light. In the tolerant line nonphotochemical quenching was induced faster and was usually about 20-30% more efficient than in the non-tolerant line. The improvement of antioxidant defense and photoprotection may be important factors in the evolutionary processes leading to tolerance to heavy metals.


Assuntos
Antioxidantes , Chlamydomonas reinhardtii , Cobre , Fluorescência , Plastoquinona , Fotossíntese , Clorofila , Peroxidases
2.
AoB Plants ; 13(1): plaa070, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33604013

RESUMO

Hybridization and introgression are important processes influencing the genetic diversity and evolution of species. These processes are of particular importance in protected areas, where they can lead to the formation of hybrids between native and foreign species and may ultimately result in the loss of parental species from their natural range. Despite their importance, the contribution of hybridization and introgression to genetic diversity in Sorbus genus remains not fully recognized. We analysed the genetic and morphological variability of several Sorbus species including native (Sorbus aria), foreign (S. intermedia) and potentially hybrid (S. carpatica) individuals from the Polish Carpathian range. Patterns of variation at 13 nuclear microsatellite loci show hybridization between the tested species and confirm the existence of the hybrid form S. carpatica. Biometric analysis on leaves, based of 10 metric features and three parameters, identified several characters for preliminary taxonomic classification; however, none of them could be used as a fully diagnostic marker for faultless annotation of S. intermedia and S. carpatica. The genetic structure analysis indicated complex patterns of population differentiation and its diverse origin. The results allow assessment of genetic variation and identification of parental species participating in hybridization. This knowledge will advance the management of genetic diversity and development of conservation strategies for efficient maintenance of the unique protected ecosystem.

3.
Acta Biochim Pol ; 67(4): 449-452, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33245659

RESUMO

Callus from Nicotiana tabacum is used as a model in plant developmental research. We tested several phytohormone (Indoleacetic acid - IAA; 2,4-Dichlorophenoxyacetic acid - 2,4-D; kinetin - KIN; 6-Benzylaminopurine - BAP) combinations to compare different approaches to callus induction directly from the seeds of Nicotiana tabacum. Callus formation was observed up to 4 weeks after sowing and the most effective were 0.5 mg/L of 2,4-D with 0.25 mg/L of BAP and 2 mg/L 2,4-D with 1 mg/L of BAP. The calli were green, photosynthetically active and after 6 weeks of growth, no stress symptoms (estimated on the basis of fluorescence of chlorophyll a in photosystem II) were noticed.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Compostos de Benzil/farmacologia , Ácidos Indolacéticos/farmacologia , Cinetina/farmacologia , Nicotiana/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Purinas/farmacologia , Clorofila A/biossíntese , Germinação/efeitos dos fármacos , Germinação/fisiologia , Células do Mesofilo/citologia , Células do Mesofilo/efeitos dos fármacos , Células do Mesofilo/metabolismo , Fotossíntese/efeitos dos fármacos , Fotossíntese/fisiologia , Plântula/citologia , Plântula/efeitos dos fármacos , Plântula/metabolismo , Sementes/citologia , Sementes/efeitos dos fármacos , Sementes/metabolismo , Nicotiana/citologia , Nicotiana/metabolismo
4.
Acta Biochim Pol ; 66(3): 257-262, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31279329

RESUMO

Chlamydomonas reinhardtii (WT 2137) P. A. Dang. (Volvocales, Chlorophyceae) is a green microalgae serving as a suitable model in scientific research and a promising industrial biotechnology platform for production of biofuel, hydrogen and recombinant proteins. Fullerenes (C60) are allotropic carbon nanoparticles discovered in 1985 and used in biomedical studies since the early 1990s, when water solubilization methodologies were developed. Recently, surface-modified hydroxylated derivatives of fullerenes were proven to enhance algal growth and drought tolerance in plants. Here, a novel type of water-soluble [60]fullerene derivative with 12 glycine residues (GF) has been synthesized and tested for acute toxicity (up to 50 µg/ml) and as a potential biostimulant of algal growth. The effects of GF on pigment composition and growth rate of Chlamydomonas reinhardtii were systematically investigated. Our results suggest that GF was not toxic, and no negative change in the pigment content and no stress symptoms were observed. No changes in the photosynthetic parameters based on the fluorescence of chlorophyll a in Photosystem II (NPQ, Fv/Fm, Fv/F0, PI and RC/ABS) were observed. The GF had no effect on cell size and growth rate. At a concentration of 20 µg/ml, GF stimulated chlorophyll accumulation in 3-day-old cultures.


Assuntos
Chlamydomonas reinhardtii/efeitos dos fármacos , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Clorofila A/metabolismo , Clorofila/metabolismo , Fulerenos/farmacologia , Biocombustíveis , Biotecnologia/métodos , Carotenoides/metabolismo , Proliferação de Células/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Fulerenos/química , Hidrogênio , Nanopartículas/química , Fotossíntese/efeitos dos fármacos , Proteínas Recombinantes , Solubilidade , Água/química
5.
Acta Biochim Pol ; 64(3): 407-413, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28892107

RESUMO

Bisphenol A (BPA) is a widely used chemical, that can potentially be toxic to plants. In this study we examined the toxicity of 5-50 mg/l of BPA on Arabidopsis thaliana. Additionally, the effects of 0.5-5 mg/l of BPA were examined after four weeks of development. BPA had no effect on the germination rate and the chlorophyll a/b ratio. The chlorophyll a and carotenoid content was significantly elevated in seedlings treated with 5 mg/l of BPA. In 4-week-old plants there was no change in the chlorophyll and carotenoid content and photosynthetic parameters (Fv/Fm, Fv/F0 and PI) were unaffected, which suggests no photoinhibition. No oxidative stress symptoms were observed. BPA significantly decreased leaf protein content. A low concentration of BPA seems to have no significant effect on A. thaliana flowering, but further investigation is needed. The results obtained indicate that a low concentration of BPA has no negative effect on the growth and development of A. thaliana.


Assuntos
Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Compostos Benzidrílicos/toxicidade , Fenóis/toxicidade , Complexo de Proteína do Fotossistema II/metabolismo , Antocianinas/metabolismo , Antioxidantes/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/metabolismo , Compostos Benzidrílicos/administração & dosagem , Carotenoides/metabolismo , Clorofila/metabolismo , Clorofila A , Relação Dose-Resposta a Droga , Poluentes Ambientais/toxicidade , Fenóis/administração & dosagem , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento
6.
Phytochemistry ; 144: 171-179, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28942064

RESUMO

Allelopathy is a phenomenon, where one species releases compounds able to inhibit the growth of other species. Juglone, 5-hydroxy-1,4-naphtoquinone, is an allelochemical produced by walnut trees. The main mode of juglone toxicity is the formation of semiquinone radicals, able to reduce O2 to superoxide. Prenyllipid antioxidants such as tocopherol and plastoquinone are important for antioxidant defense in photosynthetic organisms. Here we assess their participation in the response to juglone. The impact of 20 µM juglone on the content of photosynthetic pigments and prenyllipid antioxidants in green microalga Chlamydomonas reinhardtii was measured over an incubation period of 7.5 h in low light and over 40 min under high light or in darkness. The decrease in pigment and prenyllipid content, accompanied by an increase in lipid hydroperoxides was observed over a longer incubation period with juglone. Simultaneous exposure to high light and juglone led to a pronounced decrease in carotenoids and prenyllipids, while there was no decrease in high light alone and no decrease or only a slight decrease in the series with juglone alone. The fact that semiquinone radicals are generated in juglone-exposed cells was confirmed using EPR spectroscopy. This article also shows that C. reinhardtii may be a suitable model for studies on some modes of phytotoxic action of allelochemicals.


Assuntos
Alelopatia , Antioxidantes/metabolismo , Chlamydomonas reinhardtii/metabolismo , Naftoquinonas/metabolismo , Estresse Oxidativo , Plastoquinona/metabolismo , Tocoferóis/metabolismo , Antioxidantes/química , Carotenoides/química , Carotenoides/metabolismo , Clorofila/química , Clorofila/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Peroxidação de Lipídeos , Naftoquinonas/química , Plastoquinona/química , Tocoferóis/química
7.
Ecotoxicol Environ Saf ; 130: 133-45, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27104807

RESUMO

Acclimation to heavy metal-induced stress is a complex phenomenon. Among the mechanisms of heavy metal toxicity, an important one is the ability to induce oxidative stress, so that the antioxidant response is crucial for providing tolerance to heavy metal ions. The effect of chronic stress induced by ions of five heavy metals, Ag, Cu, Cr (redox-active metals) Cd, Hg (nonredox-active metals) on the green microalga Chlamydomonas reinhardtii was examined at two levels - the biochemical (content of photosynthetic pigments and prenyllipid antioxidants, lipid peroxidation) and the physiological (growth rate, photosynthesis and respiration rates, induction of nonphotochemical quenching of chlorophyll fluorescence). The expression of the genes which encode the enzymes participating in the detoxification of reactive oxygen species (APX1, CAT1, FSD1, MSD1) was measured. The other gene measured was one required for plastoquinone and α-tocopherol biosynthesis (VTE3). The application of heavy metal ions partly inhibited growth and biosynthesis of chlorophyll. The growth inhibition was accompanied by enhanced lipid peroxidation. An increase in the content of prenyllipid antioxidants was observed in cultures exposed to Cr2O7(2-), Cd(2+) (α- and γ-tocopherol and plastoquinone) and Cu(2+) (only tocopherols). The induction of nonphotochemical quenching was enhanced in cultures exposed to Cu(2+), Cr2O7(2-) and Cd(2+), as compared to the control. Chronic heavy metal-induced stress led to changes in gene expression dependent on the type and concentration of heavy metal ions. The up-regulation of antioxidant enzymes was usually accompanied by the up-regulation of the VTE3 gene.


Assuntos
Chlamydomonas reinhardtii/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Intoxicação por Metais Pesados , Metais Pesados/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Adaptação Fisiológica , Antioxidantes/metabolismo , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Chlamydomonas reinhardtii/metabolismo , Clorofila/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Íons/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peróxidos Lipídicos/metabolismo , Metais Pesados/análise , Metais Pesados/metabolismo , Fotossíntese/efeitos dos fármacos , Intoxicação , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Respiração/efeitos dos fármacos , Regulação para Cima
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