Publications des scientifiques de l'IRD

Brient L., Ben Gamra N., Periot M., Roumagnac M., Zeller P., Bormans M., Méjaen A., Ploux O., Biegala Isabelle. (2017). Rapid characterization of microcystin-producing cyanobacteria in freshwaterlakes by TSA-FISH (Tyramid Signal Amplification-Fluorescent in Situ Hybridization). Frontiers in Environmental Science, 5, art. no 43 [7 p. ]. ISSN 2296-665X.

Titre du document
Rapid characterization of microcystin-producing cyanobacteria in freshwaterlakes by TSA-FISH (Tyramid Signal Amplification-Fluorescent in Situ Hybridization)
Année de publication
2017
Type de document
Article
Auteurs
Brient L., Ben Gamra N., Periot M., Roumagnac M., Zeller P., Bormans M., Méjaen A., Ploux O., Biegala Isabelle
Source
Frontiers in Environmental Science, 2017, 5, art. no 43 [7 p. ] ISSN 2296-665X
Microcystin (MC) is a common and widespread toxin which represents a health hazard to humans and animals. MC toxin concentrations are monitored by various direct or proxy techniques (HPLC, LC-MS/MS, ELISA, PPIA), however, these techniques do not discriminate producing species from non-producing ones. In order to simultaneously provide the identity and activity of cyanotoxin producing species in freshwater lakes, we applied simple, and fully detailed, whole cell fluorescent in situ hybridization enhanced by tyramid signal amplification (TSA-FISH). DNA oligonucleotide probes MICR3 and MCYA were targeting 16S rRNA and mcyA-mRNA, respectively. The mcyA gene is coding for the MC synthetase enzyme involved in MC synthesis. Controls were acquired with the general eubacterial 16S rRNA probe EUB338, for TSA-FISH assay, and standard HPLC and LC-MS/MS as standard methods for the measurements of MC concentration. Results obtained from monoclonal strains and natural samples demonstrated a specific identification of Microcystis species and were able to discriminate MC producing from non-producing ones. In addition, the MCYA probe allowed the specific detection of MC-synthetase mRNA within Planktothrix isothrix (Oscillatoriale) filaments. Two kinds of mcyA-mRNA labeling were observed in these cells, spots like and plasmid like, which illustrates the well-known plasticity of microbial genome to adapt to environmental stresses. We demonstrated that a simple TSA-FISH assay allows acquiring rapidly dual information of the presence and abundance of potentially toxic species, while identifying species actively producing MC-synthetase mRNA, a proxy of MC toxin. This technique has the potential to be developed into an effective environmental monitoring tool. In addition, detail visualization of cellular mRNAs is powerful for the acquisition of ecological and biomolecular studies of toxic cyanobacteria.
Plan de classement
Biologie [020BIOL] ; Eaux continentales [036EAUCON] ; Divers [050DIVSAN]
Descripteurs
BACTERIE ; EAU DOUCE ; IDENTIFICATION ; TOXICITE ; FLUORESCENCE ; METHODE BIOLOGIQUE
Localisation
Fonds IRD [F B010072970]
Identifiant IRD
fdi:010072970
Contact