@article{MeissnerFastnerDittmannThuenemann2013,
  author    = {Meissner, Sven and Fastner, Jutta and Dittmann-Th{\"u}nemann, Elke},
  title     = {Microcystin production revisited conjugate formation makes a major contribution},
  series = {Environmental microbiology},
  volume    = {15},
  journal   = {Environmental microbiology},
  number    = {6},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {1462-2912},
  doi       = {10.1111/1462-2920.12072},
  pages     = {1810 -- 1820},
  year      = {2013},
  abstract  = {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 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.},
  language  = {en}
}