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Scenedesnus rotundus isolated from the petroleum effluent employs alternate mechanisms of tolerance to elevated levels of Cadmium and Zinc

Scenedesmus rotundus was isolated from metal contaminated petroleum industry effluent and its tolerance to Cadmium and Zinc was tested using different concentrations of CdCl(2) and ZnCl(2) ranging from 0.001 mM to 1.0 mM of Cd and 0.03 mM to 1.21 mM of Zn amended in Bolds Basal medium. The changes i...

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Autores principales: Shivaji, Subhashini, V. L. Dronamaraju, Sarada
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6560090/
https://www.ncbi.nlm.nih.gov/pubmed/31186431
http://dx.doi.org/10.1038/s41598-019-44374-1
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author Shivaji, Subhashini
V. L. Dronamaraju, Sarada
author_facet Shivaji, Subhashini
V. L. Dronamaraju, Sarada
author_sort Shivaji, Subhashini
collection PubMed
description Scenedesmus rotundus was isolated from metal contaminated petroleum industry effluent and its tolerance to Cadmium and Zinc was tested using different concentrations of CdCl(2) and ZnCl(2) ranging from 0.001 mM to 1.0 mM of Cd and 0.03 mM to 1.21 mM of Zn amended in Bolds Basal medium. The changes in cell count recorded at regular intervals upto a period of 24 days revealed a concentration dependent inhibition in growth. Concentration of the metal, at which 50% of the cells are live and metabolically active referred to as EC(50) was calculated as 0.04 mM for Cd and 0.2 mM for Zn. Further, the effect of EC(50) of the metals on the protein content, uptake of metals at varying pH, oxidative stress markers including lipid peroxidation, protein oxidation andnd oxygen uptake, levels of enzymatic antioxidants such as catalase and superoxide dismutase and non-enzymatic antioxidants namely, GSH and PC(4) were determined. Though a direct correlation could not be drawn between pH and metal uptake, the compartmentalization of the metal during the lag phase and exponential phase was evident, most of the metal was present in extracellular fractions in the former, while in the later it was internalized. Our study shows a clear correlation between toxicity of Cd and the ability of the algae to synthesize PC(4) from GSH and chelate it leading to detoxification, while Zn treatment led to an increase in the activity of catalase and superoxide dismutase and replete GSH pools. Further the changes in the cell wall structure at EC(50) of Cd and Zn were studied. This is the first report on effect of heavy metals on the structural modifications of the cell wall of Scenedesmus in general and Scenedesmus rotundus in particular, indicating appearance of granules on the entire cell surface in both Cd and Zn treatments, with the degree of granulation increasing in the order of pH 12 > 10 > 8 in Cd treatment. Further structures of higher order resembling minute wheels are observed in Cd treated cells are also reported.
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spelling pubmed-65600902019-06-19 Scenedesnus rotundus isolated from the petroleum effluent employs alternate mechanisms of tolerance to elevated levels of Cadmium and Zinc Shivaji, Subhashini V. L. Dronamaraju, Sarada Sci Rep Article Scenedesmus rotundus was isolated from metal contaminated petroleum industry effluent and its tolerance to Cadmium and Zinc was tested using different concentrations of CdCl(2) and ZnCl(2) ranging from 0.001 mM to 1.0 mM of Cd and 0.03 mM to 1.21 mM of Zn amended in Bolds Basal medium. The changes in cell count recorded at regular intervals upto a period of 24 days revealed a concentration dependent inhibition in growth. Concentration of the metal, at which 50% of the cells are live and metabolically active referred to as EC(50) was calculated as 0.04 mM for Cd and 0.2 mM for Zn. Further, the effect of EC(50) of the metals on the protein content, uptake of metals at varying pH, oxidative stress markers including lipid peroxidation, protein oxidation andnd oxygen uptake, levels of enzymatic antioxidants such as catalase and superoxide dismutase and non-enzymatic antioxidants namely, GSH and PC(4) were determined. Though a direct correlation could not be drawn between pH and metal uptake, the compartmentalization of the metal during the lag phase and exponential phase was evident, most of the metal was present in extracellular fractions in the former, while in the later it was internalized. Our study shows a clear correlation between toxicity of Cd and the ability of the algae to synthesize PC(4) from GSH and chelate it leading to detoxification, while Zn treatment led to an increase in the activity of catalase and superoxide dismutase and replete GSH pools. Further the changes in the cell wall structure at EC(50) of Cd and Zn were studied. This is the first report on effect of heavy metals on the structural modifications of the cell wall of Scenedesmus in general and Scenedesmus rotundus in particular, indicating appearance of granules on the entire cell surface in both Cd and Zn treatments, with the degree of granulation increasing in the order of pH 12 > 10 > 8 in Cd treatment. Further structures of higher order resembling minute wheels are observed in Cd treated cells are also reported. Nature Publishing Group UK 2019-06-11 /pmc/articles/PMC6560090/ /pubmed/31186431 http://dx.doi.org/10.1038/s41598-019-44374-1 Text en © The Author(s) 2019 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
spellingShingle Article
Shivaji, Subhashini
V. L. Dronamaraju, Sarada
Scenedesnus rotundus isolated from the petroleum effluent employs alternate mechanisms of tolerance to elevated levels of Cadmium and Zinc
title Scenedesnus rotundus isolated from the petroleum effluent employs alternate mechanisms of tolerance to elevated levels of Cadmium and Zinc
title_full Scenedesnus rotundus isolated from the petroleum effluent employs alternate mechanisms of tolerance to elevated levels of Cadmium and Zinc
title_fullStr Scenedesnus rotundus isolated from the petroleum effluent employs alternate mechanisms of tolerance to elevated levels of Cadmium and Zinc
title_full_unstemmed Scenedesnus rotundus isolated from the petroleum effluent employs alternate mechanisms of tolerance to elevated levels of Cadmium and Zinc
title_short Scenedesnus rotundus isolated from the petroleum effluent employs alternate mechanisms of tolerance to elevated levels of Cadmium and Zinc
title_sort scenedesnus rotundus isolated from the petroleum effluent employs alternate mechanisms of tolerance to elevated levels of cadmium and zinc
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6560090/
https://www.ncbi.nlm.nih.gov/pubmed/31186431
http://dx.doi.org/10.1038/s41598-019-44374-1
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