Although both Astasia longa and Euglena gracilis belong to different genera, they share many morphological characters except that A. longa has no chloroplast. In the 1940’s, on the basis of the finding that in darkne...Although both Astasia longa and Euglena gracilis belong to different genera, they share many morphological characters except that A. longa has no chloroplast. In the 1940’s, on the basis of the finding that in darkness or upon addition of some chemicals, E. gracilis would fade reversibly or irreversibly, some scholars hypothesised that A. longa evolved from E. gracilis by losing chloroplast. The authors’ use of RAPD and cladistic analyses in a study on the evolutionary relationship between A .longa and E. gracilis showed that the A. longa ’s relationship with E. gracilis was closer than that with other green euglenoids. This proves the hypothesis that A. longa evolved from E. gracilis is reasonable. The results of this study suggest that saprophytic colorless euglenoids were transformed from green euglenoids by losing their choroplasts.展开更多
External micro-PIXE measurements were done to investigate the accumulation of Nd^(3+)on green algae species euglena gracilis.According to the Nd distribution patterns in the gracilis cells,the biosorption of Nd^(3+)to...External micro-PIXE measurements were done to investigate the accumulation of Nd^(3+)on green algae species euglena gracilis.According to the Nd distribution patterns in the gracilis cells,the biosorption of Nd^(3+)to the cell's compartments can be observed.Comparing elemental mappings of the cell treated with different doses of the 1 mg/mL Nd^(3+)solution,the Nd uptake of euglena gracilis cells do no relate with the doses.From distributions of Ca and Mg,it is found that the Ca is complementary to Nd partly,and the Nd and Mg distributions are alike to each other,showing that Nd may be mainly in the chlorophyll molecules.The biochemistry related is discussed.展开更多
文摘Although both Astasia longa and Euglena gracilis belong to different genera, they share many morphological characters except that A. longa has no chloroplast. In the 1940’s, on the basis of the finding that in darkness or upon addition of some chemicals, E. gracilis would fade reversibly or irreversibly, some scholars hypothesised that A. longa evolved from E. gracilis by losing chloroplast. The authors’ use of RAPD and cladistic analyses in a study on the evolutionary relationship between A .longa and E. gracilis showed that the A. longa ’s relationship with E. gracilis was closer than that with other green euglenoids. This proves the hypothesis that A. longa evolved from E. gracilis is reasonable. The results of this study suggest that saprophytic colorless euglenoids were transformed from green euglenoids by losing their choroplasts.
基金Supported by a grant from the Frontier Science Projects Program of the Institute of Hydrobiology,the Chinese Academy of Sciences(No.220207)the Foundation of State Key Laboratory of Freshwater Ecology and Biotechnology(No.2005FB13)
基金Supported by the National Natural Science Foundation of China(Nos.10675033 and 10975034)
文摘External micro-PIXE measurements were done to investigate the accumulation of Nd^(3+)on green algae species euglena gracilis.According to the Nd distribution patterns in the gracilis cells,the biosorption of Nd^(3+)to the cell's compartments can be observed.Comparing elemental mappings of the cell treated with different doses of the 1 mg/mL Nd^(3+)solution,the Nd uptake of euglena gracilis cells do no relate with the doses.From distributions of Ca and Mg,it is found that the Ca is complementary to Nd partly,and the Nd and Mg distributions are alike to each other,showing that Nd may be mainly in the chlorophyll molecules.The biochemistry related is discussed.
