Microcystin production revisited conjugate formation makes a major contribution
- The impact of environmental stimuli on the production of the widespread cyanobacterial hepatotoxin microcystin (MC) is under debate. Whereas transcriptional studies of the biosynthetic genes suggest a clear influence of light conditions on toxin production the data for the metabolite itself are inconsistent and highly strain-specific. Here, we have reassessed the MC content by using two immunological detection techniques that allow a parallel quantification of MC in the methanolic extracts and the residual pellet fraction that contains high molecular weight proteins. Our results show a significant proportion of MC in the protein bound fraction in strains of Microcystis and Planktothrix and of the related toxin nodularin (NOD) in Nodularia. Moreover, we could show a very strong increase of MC after high light illumination in the protein fraction contributing to a significant overall increase in MC production under these conditions that is not seen in extracts analysed by LC-MS and ELISA. The fact that a considerable portion of MC isThe impact of environmental stimuli on the production of the widespread cyanobacterial hepatotoxin microcystin (MC) is under debate. Whereas transcriptional studies of the biosynthetic genes suggest a clear influence of light conditions on toxin production the data for the metabolite itself are inconsistent and highly strain-specific. Here, we have reassessed the MC content by using two immunological detection techniques that allow a parallel quantification of MC in the methanolic extracts and the residual pellet fraction that contains high molecular weight proteins. Our results show a significant proportion of MC in the protein bound fraction in strains of Microcystis and Planktothrix and of the related toxin nodularin (NOD) in Nodularia. Moreover, we could show a very strong increase of MC after high light illumination in the protein fraction contributing to a significant overall increase in MC production under these conditions that is not seen in extracts analysed by LC-MS and ELISA. The fact that a considerable portion of MC is neglected with current analysis techniques was also confirmed for selected field samples. Immunofluorescence studies suggest strain-specific differences in the amount of MC conjugate formation.…
Author details: | Sven Meissner, Jutta Fastner, Elke Dittmann-ThünemannORCiDGND |
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DOI: | https://doi.org/10.1111/1462-2920.12072 |
ISSN: | 1462-2912 |
Title of parent work (English): | Environmental microbiology |
Publisher: | Wiley-Blackwell |
Place of publishing: | Hoboken |
Publication type: | Article |
Language: | English |
Year of first publication: | 2013 |
Publication year: | 2013 |
Release date: | 2017/03/26 |
Volume: | 15 |
Issue: | 6 |
Number of pages: | 11 |
First page: | 1810 |
Last Page: | 1820 |
Funding institution: | German Research Foundation [Di910/3-1] |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Biochemie und Biologie |
Peer review: | Referiert |