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https://hdl.handle.net/1822/32110
Título: | Modification of cell volume and proliferative capacity of Pseudokirchneriella subcapitata cells exposed to heavy metal stress |
Autor(es): | Machado, Manuela D. Soares, Eduardo V. |
Palavras-chave: | Algal growth Biovolume Cell division Cell proliferation Cell size Metal toxicity |
Data: | 2014 |
Editora: | Elsevier B.V. |
Revista: | Aquatic Toxicology |
Citação: | Machado, Manuela D.; Soares, Eduardo V., Modification of cell volume and proliferative capacity of Pseudokirchneriella subcapitata cells exposed to heavy metal stress. Aquatic Toxicology, 147, 1-6, 2014 |
Resumo(s): | The impact of metals (Cd, Cr, Cu and Zn) on growth, cell volume and cell division of the freshwater alga Pseudokirchneriella subcapitata exposed over a period of 72 h was investigated. The algal cells were exposed to three nominal concentrations of each metal: low (closed to 72 h-EC10 values), intermediate (closed to 72 h-EC50 values) and high (upper than 72 h-EC90 values). The exposure to low metal concentrations resulted in a decrease of cell volume. On the contrary, for the highest metal concentrations an increase of cell volume was observed; this effect was particularly notorious for Cd and less pronounced for Zn. Two behaviours were found when algal cells were exposed to intermediate concentrations of metals: Cu(II) and Cr(VI) induced a reduction of cell volume, while Cd(II) and Zn(II) provoked an opposite effect. The simultaneous nucleus staining and cell image analysis, allowed distinguishing three phases in P. subcapitata cell cycle: growth of mother cell; cell division, which includes two divisions of the nucleus; and, release of four autospores. The exposure of P. subcapitata cells to the highest metal concentrations resulted in the arrest of cell growth before the first nucleus division [for Cr(VI) and Cu(II)] or after the second nucleus division but before the cytokinesis (release of autospores) when exposed to Cd(II). The different impact of metals on algal cell volume and cell-cycle progression, suggests that different toxicity mechanisms underlie the action of different metals studied. The simultaneous nucleus staining and cell image analysis, used in the present work, can be a useful tool in the analysis of the toxicity of the pollutants, in P. subcapitata, and help in the elucidation of their different modes of action. |
Tipo: | Artigo |
URI: | https://hdl.handle.net/1822/32110 |
DOI: | 10.1016/j.aquatox.2013.11.017 |
ISSN: | 1879-1514 |
e-ISSN: | 0166-445X |
Versão da editora: | www.elsevier.com/locate/aquatox |
Arbitragem científica: | yes |
Acesso: | Acesso aberto |
Aparece nas coleções: | CEB - Publicações em Revistas/Séries Internacionais / Publications in International Journals/Series |
Ficheiros deste registo:
Ficheiro | Descrição | Tamanho | Formato | |
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document_17064_1.pdf | 879,13 kB | Adobe PDF | Ver/Abrir |