کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4545938 1327479 2009 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Response of cylindrospermopsin production and release in Aphanizomenon flos-aquae (Cyanobacteria) to varying light and temperature conditions
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم آبزیان
پیش نمایش صفحه اول مقاله
Response of cylindrospermopsin production and release in Aphanizomenon flos-aquae (Cyanobacteria) to varying light and temperature conditions
چکیده انگلیسی

The influence of light and temperature on the cylindrospermopsin (CYN) production of two Aphanizomenon flos-aquae strains, isolated from North-eastern German lakes, was investigated with semi-continuously growing cultures. A light gradient from 10 to 60 μE m−2 s−1 in combination with temperatures of 16, 20, and 25 °C was tested.CYN concentrations varied by a maximum factor of 2.7 in strain 10E9 with a significant decrease with increasing temperature. Strain 22D11 showed less pronounced changes, i.e. by a factor of 1.6, and without clear relationship to temperature.Reaction patterns of CYN production to changing light intensities are different at different temperatures. In both strains CYN concentrations increase significantly at 20 °C between 10 and 60 μE m−2 s−1, whereas they decrease significantly at 25 °C in the same light gradient. The amount of synthesised CYN is not reflected by growth rates of the strains in a uniform manner. Nonetheless several temperature–light combinations which constitute physiological stress seem to trigger CYN production and particularly CYN release from cells. The lowest growth rate observed at 16 °C and 60 μE m−2 s−1 of strain 22D11 may reflect photoinhibition due to the lower temperature and related limited CO2-fixation. Under these conditions, extracellular CYN concentrations increased to 58% of total CYN, while the share of extracellular CYN of all other light and temperature regimes was 11–26%. From the results and the experimental design we conclude an active release of the toxin into medium to be more likely than mere leakage from cells.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Harmful Algae - Volume 8, Issue 5, June 2009, Pages 645–650
نویسندگان
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