Cyanobactéries / algues bleues

Les cyanobactéries, également appelées algues bleues, font partie des bactéries et des formes de vie productrices d'oxygène les plus anciennes de la planète. Composantes naturelles des écosystèmes aquatiques, elles sont présentes dans presque tous les plans d'eau et dans de nombreux sites humides à travers le monde, y compris en Suisse. Certaines espèces peuvent toutefois produire des toxines (cyanotoxines) dangereuses pour les êtres humains et les animaux. Les chercheur·euse·s de l'Eawag s'efforcent donc de mieux comprendre l'écologie des cyanobactéries toxiques afin de mieux prévoir leur apparition et d'évaluer les risques qu'elles présentent.


Les cyanobactéries sont souvent appelées algues bleues en raison de leur couleur, qui provient des pigments chlorophylle (vert) et phycocyanine (bleu) utilisés pour la photosynthèse. Selon l'espèce, elles peuvent toutefois également être vertes, jaunes, brunes ou rouges. Longtemps considérées comme des algues, les chercheur·euse·s ont découvert par la suite qu'il s'agissait en réalité de bactéries, d'où leur nom correct de cyanobactéries. Pour identifier les cyanobactéries, les spécialistes utilisent généralement des microscopes.

Les cyanobactéries sont parmi les premiers organismes à avoir pu produire leur énergie par photosynthèse et à avoir ainsi libéré le premier oxygène dans l'atmosphère. Il existe plusieurs milliers d'espèces de cyanobactéries sur Terre, et elles constituent l'un des micro-organismes photosynthétiques les plus courants dans les océans et les eaux douces.

À ce jour, on connaît environ 40 espèces de cyanobactéries qui produisent des métabolites toxiques (cyanotoxines). Le changement climatique favorise de plus en plus la prolifération massive de cyanobactéries, ce qui représente un danger pour les écosystèmes et la santé de la population.

Où trouver des cyanobactéries dans l'eau

Selon l'endroit où elles se multiplient dans les eaux de surface, on distingue les cyanobactéries pélagiques et benthiques.

Proliférations pélagiques dans la colonne d'eau

En eau libre, dans la zone pélagique, les cyanobactéries peuvent se multiplier en masse en cas de fort ensoleillement, de chaleur et de nutriments (azote et phosphore) suffisants, entraînant une «prolifération». Ces proliférations flottent à différentes profondeurs dans les lacs et ne sont donc pas toujours immédiatement visibles. Certaines cyanobactéries peuvent remonter activement à la surface. Le mélange saisonnier de l'eau ou des vents forts peuvent également amener passivement les cyanobactéries à la surface de l'eau. Lorsque la biomasse remonte à la surface, les cyanobactéries sont facilement reconnaissables. Il est alors recommandé aux humains et aux animaux de ne pas entrer en contact avec elles.

Apparence : une turbidité ou une coloration bleue, verte, jaune ou rouge de l'eau indique une forte concentration en cyanobactéries. Des stries, des tapis de mousse, des flocons ou des grumeaux peuvent se former.

Occurrence : les proliférations de cyanobactéries dans la colonne d'eau surviennent principalement à la fin de l'été et en automne, mais peuvent également être visibles en hiver/au printemps, selon les espèces.

Toxines : les microcystines, qui agissent comme des toxines hépatiques (hépatotoxines), constituent la classe de substances la plus connue et la mieux étudiée. Ces microcystines sont produites par de nombreuses cyanobactéries pélagiques.

Danger : les jeunes enfants et les chiens courent un risque particulier en cas d'ingestion de biomasse ou de contact prolongé avec de l'eau contenant des concentrations élevées de cyanotoxines. Cela peut entraîner des irritations cutanées, des vomissements ou des difficultés respiratoires.

 

Tapis benthiques au fond

Les cyanobactéries ne se développent pas seulement dans les eaux calmes et ouvertes, mais aussi au fond des cours d'eau, des mares ou des lacs, dans la zone benthique. Elles y forment un biofilm sur les pierres, les morceaux de bois ou les plantes aquatiques, appelées tapis benthiques (également appelés «peaux de crapaud»).

Contrairement aux proliférations dans les eaux ouvertes, les tapis benthiques peuvent également se former dans des eaux pauvres en nutriments, claires ou peu troubles, qui laissent passer la lumière du soleil jusqu'au fond.

Apparence : ces tapis peuvent avoir une épaisseur de plusieurs millimètres à plusieurs centimètres et se former souvent à l'insu au fond de l'eau. Les tapis benthiques sont de couleur brune, noire, vert foncé ou rouge foncé et présentent parfois des bulles d'air à la surface, qui sont le résultat de la photosynthèse et contribuent à ce que les tapis ou des fragments de ceux-ci se détachent du fond et remontent à la surface. Les morceaux dérivent alors vers la surface de l'eau ou vers la rive. Lorsqu'ils sèchent sur la rive, ils prennent souvent une couleur grise ou brune.

Occurrence : contrairement aux proliférations pélagiques, les tapis benthiques apparaissent également dans les cours d'eau et peuvent poser des problèmes du printemps jusqu’à la fin de l'automne.

Toxines : les cyanobactéries benthiques peuvent parfois produire des neurotoxines très puissantes. Celles-ci appartiennent à la classe des anatoxines. Les anatoxines sont à l'origine de décès soudains chez les chiens en Suisse et dans le monde entier.
Danger : les chiens sont attirés par l'odeur putride des tapis et peuvent absorber des toxines lorsqu'ils boivent de l'eau, rongent des morceaux de bois ou se lèchent le pelage. La concentration en neurotoxines peut être très élevée dans les tapis benthiques, même si elle est généralement à peine détectable dans l'eau libre qui les entoure. L'ingestion de faibles quantités peut déjà être mortelle pour les chiens. Les jeunes enfants peuvent également jouer avec les débris sur la rive et les avaler accidentellement.

Vidéo: Drone sous-marin pour la détection des cyanobactéries

Les chercheur·euse·s de l'Eawag utilisent le BlueROV (Remotely Operated Vehicle) pour détecter les tapis de cyanobactéries et observer leur croissance au cours de l'année. Après la recherche, les échantillons sont envoyés au laboratoire afin d'analyser leur toxicité potentielle.

Aquascope – Images en direct du microscope sous-marin


Le microscope sous-marin adapté à l'eau douce de l'Eawag fournit (actuellement depuis les lacs de Greifen et de Zoug) des images du plancton presque en temps réel. Plongez dans le monde miniature autrement caché des algues (y compris les cyanobactéries), des puces d'eau, des petits crustacés et autres : www.aquascope.ch  

Pour une classification en temps réel du lac de Greifen

Galerie de photos

Expertes et experts

Dr. Francesco Pomati
  • algues
  • biodiversité
  • ecologie
  • plancton
  • ecotoxicologie
PD Dr. Elisabeth Janssen
  • photochimie
  • polluants organiques
  • algues
  • dégradation biologique

Publications académiques

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   0 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=22310, pid=124)
      originalId => protected22310 (integer)
      authors => protected'Jones, M. R.; Pinto, E.; Torres, M. A.; Dörr,&nbsp
         ;F.; Mazur-Marzec, H.; Szubert, K.; Tartaglione, L.; Dell'Ave
         rsano, C.; Miles, C. O.; Beach, D. G.; McCarron,&nb
         sp;P.; Sivonen, K.; Fewer, D. P.; Jokela, J.; Janssen,&n
         bsp;E. M. -L.
' (327 chars) title => protected'CyanoMetDB, a comprehensive public database of secondary metabolites from cy
         anobacteria
' (87 chars) journal => protected'Water Research' (14 chars) year => protected2021 (integer) volume => protected196 (integer) issue => protected'' (0 chars) startpage => protected'117017 (12 pp.)' (15 chars) otherpage => protected'' (0 chars) categories => protected'cyanobacteria; secondary metabolite; database; toxin; cyanopeptide; CyanoMet
         DB
' (78 chars) description => protected'Harmful cyanobacterial blooms, which frequently contain toxic secondary meta
         bolites, are reported in aquatic environments around the world. More than tw
         o thousand cyanobacterial secondary metabolites have been reported from dive
         rse sources over the past fifty years. A comprehensive, publically-accessibl
         e database detailing these secondary metabolites would facilitate research i
         nto their occurrence, functions and toxicological risks. To address this nee
         d we created CyanoMetDB, a highly curated, flat-file, openly-accessible data
         base of cyanobacterial secondary metabolites collated from 850 peer-reviewed
          articles published between 1967 and 2020. CyanoMetDB contains 2010 cyanobac
         terial metabolites and 99 structurally related compounds. This has nearly do
         ubled the number of entries with complete literature metadata and structural
          composition information compared to previously available open access databa
         ses. The dataset includes microcytsins, cyanopeptolins, other depsipeptides,
          anabaenopeptins, microginins, aeruginosins, cyclamides, cryptophycins, saxi
         toxins, spumigins, microviridins, and anatoxins among other metabolite class
         es. A comprehensive database dedicated to cyanobacterial secondary metabolit
         es facilitates: (1) the detection and dereplication of known cyanobacterial
         toxins and secondary metabolites; (2) the identification of novel natural pr
         oducts from cyanobacteria; (3) research on biosynthesis of cyanobacterial se
         condary metabolites, including substructure searches; and (4) the investigat
         ion of their abundance, persistence, and toxicity in natural environments.
' (1594 chars) serialnumber => protected'0043-1354' (9 chars) doi => protected'10.1016/j.watres.2021.117017' (28 chars) uid => protected22310 (integer) _localizedUid => protected22310 (integer)modified _languageUid => protectedNULL _versionedUid => protected22310 (integer)modified pid => protected124 (integer)
1 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=33751, pid=124) originalId => protected33751 (integer) authors => protected'Pittino, F.; Fink, S.; Oliveira, J.; Janssen, E. M.
          L.; Scheidegger, C.
' (106 chars) title => protected'Lithic bacterial communities: ecological aspects focusing on <em>Tintenstric
         h</em> communities
' (94 chars) journal => protected'Frontiers in Microbiology' (25 chars) year => protected2024 (integer) volume => protected15 (integer) issue => protected'' (0 chars) startpage => protected'1430059 (12 pp.)' (16 chars) otherpage => protected'' (0 chars) categories => protected'cyanobacteria; Tintenstrich; lithic bacterial communities; extreme environme
         nts; lichens
' (88 chars) description => protected'<em>Tintenstrich</em> communities (TCs) mainly comprise Cyanobacteria develo
         ping on rock substrates and forming physical structures that are strictly co
         nnected to the rock itself. Endolithic and epilithic bacterial communities a
         re important because they contribute to nutrient release within run-off wate
         rs flowing on the rock surface. Despite TCs being ubiquitous, little informa
         tion about their ecology and main characteristics is available. In this stud
         y, we characterized the bacterial communities of rock surfaces of TCs in Swi
         tzerland through Illumina sequencing. We investigated their bacterial commun
         ity composition on two substrate types (siliceous rocks [SRs] and carbonate
         rocks [CRs]) through multivariate models. Our results show that Cyanobacteri
         a and Proteobacteria are the predominant phyla in this environment. Bacteria
         l <em>α</em>-diversity was higher on CRs than on SRs, and the <em>β</em>-d
         iversity of SRs varied with changes in rock surface structure. In this study
         , we provide novel insights into the bacterial community composition of TCs,
          their differences from other lithic communities, and the effects of the roc
         k substrate and structure.
' (1166 chars) serialnumber => protected'' (0 chars) doi => protected'10.3389/fmicb.2024.1430059' (26 chars) uid => protected33751 (integer) _localizedUid => protected33751 (integer)modified _languageUid => protectedNULL _versionedUid => protected33751 (integer)modified pid => protected124 (integer)
2 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=33024, pid=124) originalId => protected33024 (integer) authors => protected'Rougé,&nbsp;V.; von Gunten,&nbsp;U.; Janssen,&nbsp;E.&nbsp;M.&nbsp;L.' (70 chars) title => protected'Reactivity of cyanobacteria metabolites with ozone: multicompound competitio
         n kinetics
' (86 chars) journal => protected'Environmental Science and Technology' (36 chars) year => protected2024 (integer) volume => protected58 (integer) issue => protected'26' (2 chars) startpage => protected'11802' (5 chars) otherpage => protected'11811' (5 chars) categories => protected'cyanopeptides; planktothrix; microcystis; micropollutant; ozonation; toxins;
          microcystin
' (88 chars) description => protected'Cyanobacterial blooms occur at increasing frequency and intensity, notably i
         n freshwater. This leads to the introduction of complex mixtures of their pr
         oducts, i.e., cyano-metabolites, to drinking water treatment plants. To asse
         ss the fate of cyano-metabolite mixtures during ozonation, a novel multicomp
         ound ozone (O<sub>3</sub>) competition kinetics method was developed. Sixtee
         n competitors with known second-order rate constants for their reaction with
         
         
         . The apparent second-order rate constants (<em>k</em><sub>app,O3</sub>) at
         pH 7 were simultaneously determined for 31 cyano-metabolites. <em>k</em><sub
         >app,O3</sub> for olefin- and phenol-containing cyano-metabolites were consi
         stent with their expected reactivity (0.4–1.7 × 10<sup>6</sup> M<sup>–1
         </sup> s<sup>–1</sup>) while <em>k</em><sub>app,O3</sub> for tryptophan- a
         nd thioether-containing cyano-metabolites were significantly higher than exp
         ected (3.4–7.3 × 10<sup>7</sup> M<sup>–1</sup> s<sup>–1</sup>). Cyano
         -metabolites containing these moieties are predicted to be well abated durin
         g ozonation. For cyano-metabolites containing heterocycles, <em>k</em><sub>a
         
         
         tivity of this class of compounds. Due to lower O<sub>3</sub> reactivities,
         heterocycle- and aliphatic amine-containing cyano-metabolites may be only pa
         rtially degraded by a direct O<sub>3</sub> reaction near circumneutral pH. H
         ydroxyl radicals, which are formed during ozonation, may be more important f
         or their abatement. This novel multicompound kinetic method allows a high-th
         roughput screening of ozonation kinetics.
' (1865 chars) serialnumber => protected'0013-936X' (9 chars) doi => protected'10.1021/acs.est.4c02242' (23 chars) uid => protected33024 (integer) _localizedUid => protected33024 (integer)modified _languageUid => protectedNULL _versionedUid => protected33024 (integer)modified pid => protected124 (integer)
3 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=33003, pid=124) originalId => protected33003 (integer) authors => protected'Torres,&nbsp;M.&nbsp;de&nbsp;A.; Dax,&nbsp;A.; Grand,&nbsp;I.; vom Berg,&nbs
         p;C.; Pinto,&nbsp;E.; Janssen,&nbsp;E.&nbsp;M..L.
' (127 chars) title => protected'Lethal and behavioral effects of semi-purified microcystins, Micropeptin and
          apolar compounds from cyanobacteria on freshwater microcrustacean Thamnocep
         halus platyurus
' (167 chars) journal => protected'Aquatic Toxicology' (18 chars) year => protected2024 (integer) volume => protected273 (integer) issue => protected'' (0 chars) startpage => protected'106983 (9 pp.)' (14 chars) otherpage => protected'' (0 chars) categories => protected'cyanobacterial metabolites; grazer toxicity; malformation; locomotor behavio
         ur; cyanopeptolin; microginin
' (105 chars) description => protected'The mass proliferation of cyanobacteria, episodes known as blooms, is a conc
         ern worldwide. One of the most critical aspects during these blooms is the p
         roduction of toxic secondary metabolites that are not limited to the four cy
         anotoxins recognized by the World Health Organization. These metabolites com
         prise a wide range of structurally diverse compounds that possess bioactive
         functions. Potential human and ecosystem health risks posed by these metabol
         ites and co-produced mixtures remain largely unknown. We studied acute letha
         l and sublethal effects measured as impaired mobility on the freshwater micr
         ocrustaceans Thamnocephalus platyurus for metabolite mixtures from two cyano
         bacterial strains, a microcystin (MC) producer and a non-MC producer. Both c
         yanobacterial extracts, from the MC-producer and non-MC-producer, caused acu
         te toxicity with LC<sub>50</sub> (24 h) values of 0.50 and 2.55 mg<sub>dw_bi
         omass</sub>/mL, respectively, and decreased locomotor activity. Evaluating t
         he contribution of different cyanopeptides revealed that the Micropeptin-K13
         9-dominated fraction from the MC-producer extract contributed significantly
         to mortality and locomotor impairment of the microcrustaceans, with potentia
         l mixture effect with other cyanopeptolins present in this fraction. In the
         non-MC-producer extract, compounds present in the apolar fraction contribute
         d mainly to mortality, locomotor impairment, and morphological changes in th
         e antennae of the microcrustacean. No lethal or sublethal effects were obser
         ved in the fractions dominated by other cyanopetides (Cyanopeptolin 959, Nos
         toginin BN741). Our findings contribute to the growing body of research indi
         cating that cyanobacterial metabolites beyond traditional cyanotoxins cause
         detrimental effects. This underscores the importance of toxicological assess
         ments of such compounds, also at sublethal levels.
' (1874 chars) serialnumber => protected'0166-445X' (9 chars) doi => protected'10.1016/j.aquatox.2024.106983' (29 chars) uid => protected33003 (integer) _localizedUid => protected33003 (integer)modified _languageUid => protectedNULL _versionedUid => protected33003 (integer)modified pid => protected124 (integer)
4 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=31895, pid=124) originalId => protected31895 (integer) authors => protected'de Almeida Torres,&nbsp;M.; Jones,&nbsp;M.&nbsp;R.; vom Berg,&nbsp;C.; Pinto
         ,&nbsp;E.; Janssen,&nbsp;E.&nbsp;M.&nbsp;-L.
' (120 chars) title => protected'Lethal and sublethal effects towards zebrafish larvae of microcystins and ot
         her cyanopeptides produced by cyanobacteria
' (119 chars) journal => protected'Aquatic Toxicology' (18 chars) year => protected2023 (integer) volume => protected263 (integer) issue => protected'' (0 chars) startpage => protected'106689 (11 pp.)' (15 chars) otherpage => protected'' (0 chars) categories => protected'cyanobacterial metabolites; fish toxicity; cardiotoxicity; locomotor behavio
         ur; cyanopeptolin; microginin
' (105 chars) description => protected'Cyanobacterial blooms affect aquatic ecosystems across the globe and one maj
         or concern relates to their toxins such as microcystins (MC). Yet, the ecoto
         xicological risks, particularly non-lethal effects, associated with other co
         -produced secondary metabolites remain mostly unknown. Here, we assessed sur
         vival, morphological alterations, swimming behaviour and cardiovascular func
         tions of zebrafish (<em>Danio rerio</em>) upon exposure to cyanobacterial ex
         tracts of two Brazilian <em>Microcystis</em> strains. We verified that only
         MIRS-04 produced MCs and identified other co-produced cyanopeptides also for
          the MC non-producer NPCD-01 by LC-HRMS/MS analysis. Both cyanobacterial ext
         racts, from the MC-producer and non-producer, caused acute toxicity in zebra
         fish with LC<sub>50</sub> values of 0.49 and 0.98 mg<sub>dw_biomass</sub>/mL
         , respectively. After exposure to MC-producer extract, additional decreased
         locomotor activity was observed. The cyanopeptolin (micropeptin K139) contri
         buted 52% of the overall mortality and caused oedemas of the pericardial reg
         ion. Oedemas of the pericardial area and prevented hatching were also observ
         ed upon exposure to the fraction with high abundance of a microginin (Nostog
         inin BN741) in the extract of the MC non-producer. Our results further add t
         o the yet sparse understanding of lethal and sublethal effects caused by cya
         nobacterial metabolites other than MCs and the need to better understand the
          underlying mechanisms of the toxicity. We emphasize the importance of consi
         dering mixture toxicity of co-produced metabolites in the ecotoxicological r
         isk assessment of cyanobacterial bloom events, given the importance for pred
         icting adverse outcomes in fish and other organisms.
' (1724 chars) serialnumber => protected'0166-445X' (9 chars) doi => protected'10.1016/j.aquatox.2023.106689' (29 chars) uid => protected31895 (integer) _localizedUid => protected31895 (integer)modified _languageUid => protectedNULL _versionedUid => protected31895 (integer)modified pid => protected124 (integer)
5 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=33271, pid=124) originalId => protected33271 (integer) authors => protected'Wang,&nbsp;X.; Wullschleger,&nbsp;S.; Jones,&nbsp;M.; Reyes,&nbsp;M.; Bossar
         t,&nbsp;R.; Pomati,&nbsp;F.; Janssen,&nbsp;E.&nbsp;M.&nbsp;-L.
' (138 chars) title => protected'Tracking extensive portfolio of cyanotoxins in five-year lake survey and ide
         ntifying indicator metabolites of cyanobacterial taxa
' (129 chars) journal => protected'Environmental Science and Technology' (36 chars) year => protected2024 (integer) volume => protected58 (integer) issue => protected'37' (2 chars) startpage => protected'16560' (5 chars) otherpage => protected'16569' (5 chars) categories => protected'microcystin; suspect screening; monitoring; cyanopepetides; harmful algal bl
         oom
' (79 chars) description => protected'Cyanobacterial blooms require monitoring, as they pose a threat to ecosystem
         s and human health, especially by the release of toxins. Along with widely r
         eported microcystins, cyanobacteria coproduce other bioactive metabolites; h
         owever, information about their dynamics in surface waters is sparse. We inv
         estigated dynamics across full bloom successions throughout a five-year lake
          monitoring campaign (Greifensee, Switzerland) spanning 150 sampling dates.
         We conducted extensive suspect screening of cyanobacterial metabolites using
          the database CyanoMetDB. Across all 850 samples, 35 metabolites regularly c
         o-occurred. Microcystins were present in 70% of samples, with [d-Asp<sup>3</
         sup>,(<em>E</em>)-Dhb<sup>7</sup>]MC-RR reaching concentrations of 70 ng/L.
         Anabaenopeptins, meanwhile, were detected in 95% of all samples with concent
         rations of Oscillamide Y up to 100-fold higher than microcystins. Based on L
         C-MS response and frequency, we identified indicator metabolites exclusively
          produced by one of three cyanobacteria isolated from the lake, these being
         [d-Asp<sup>3</sup>,(<em>E</em>)-Dhb<sup>7</sup>]MC-RR from <em>Planktothrix<
         /em> sp. G2020, Microginin 761B from <em>Microcystis</em> sp. G2011, and Fer
         intoic acid B from <em>Microcystis</em> sp. G2020. These indicators showed d
         istinct temporal trends and peaking seasons that reflect the variance in eit
         her the abundance of the producing cyanobacteria or their toxin production d
         ynamics. Our approach demonstrates that selecting high LC-MS response and fr
         equent and species-specific indicator metabolites can be advantageous for cy
         anobacterial monitoring.
' (1620 chars) serialnumber => protected'0013-936X' (9 chars) doi => protected'10.1021/acs.est.4c04813' (23 chars) uid => protected33271 (integer) _localizedUid => protected33271 (integer)modified _languageUid => protectedNULL _versionedUid => protected33271 (integer)modified pid => protected124 (integer)
6 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=34638, pid=124) originalId => protected34638 (integer) authors => protected'Eyring,&nbsp;S.; Reyes,&nbsp;M.; Merz,&nbsp;E.; Baity-Jesi,&nbsp;M.; Ntetsik
         a,&nbsp;P.; Ebi,&nbsp;C.; Dennis,&nbsp;S.; Pomati,&nbsp;F.
' (134 chars) title => protected'Five years of high-frequency data of phytoplankton zooplankton and limnology
          from a temperate eutrophic lake
' (108 chars) journal => protected'Scientific Data' (15 chars) year => protected2025 (integer) volume => protected12 (integer) issue => protected'1' (1 chars) startpage => protected'653 (13 pp.)' (12 chars) otherpage => protected'' (0 chars) categories => protected'' (0 chars) description => protected'This study presents a comprehensive dataset from Lake Greifen, Switzerland,
         collected between April 2018 and June 2023, using high-frequency automated m
         onitoring systems. The dataset integrates meteorological data, nutrient chem
         istry, water column profiles for water physics, and plankton underwater imag
         ing, offering insights into the lake's physical and biological processes. A
         dual-magnification dark field underwater microscope captured hourly plankton
          dynamics at 3 m depth, providing size, shape, and taxonomic information.
         A profiler with a multiparametric probe monitored water temperature, oxygen,
          and other key parameters from 1 to 17 m depth, while weekly nutrient samp
         ling complemented the measurements. Data processing involved rigorous cleani
         ng protocols to remove technical artefacts, ensuring data quality. Our datas
         et showcases the utility of integrating different approaches for high-freque
         ncy monitoring to detect lake temporal processes, from phytoplankton blooms
         to zooplankton vertical migration and seasonal shifts in water column stabil
         ity. This dataset provides a unique resource for studying limnology and plan
         kton community ecology. All data and related processing codes are publicly a
         vailable for further research, supporting interdisciplinary studies.
' (1284 chars) serialnumber => protected'' (0 chars) doi => protected'10.1038/s41597-025-04988-9' (26 chars) uid => protected34638 (integer) _localizedUid => protected34638 (integer)modified _languageUid => protectedNULL _versionedUid => protected34638 (integer)modified pid => protected124 (integer)
7 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=18207, pid=124) originalId => protected18207 (integer) authors => protected'Janssen,&nbsp;E.&nbsp;M.&nbsp;-L.' (33 chars) title => protected'Cyanobacterial peptides beyond microcystins – a review on co-occurrence, t
         oxicity, and challenges for risk assessment
' (119 chars) journal => protected'Water Research' (14 chars) year => protected2019 (integer) volume => protected151 (integer) issue => protected'' (0 chars) startpage => protected'488' (3 chars) otherpage => protected'499' (3 chars) categories => protected'harmful algal bloom; cyanobacteria; toxin; risk assessment; ecotoxicology; h
         uman health
' (87 chars) description => protected'Cyanobacterial bloom events that produce natural toxins occur in freshwaters
          across the globe, yet the potential risk of many cyanobacterial metabolites
          remains mostly unknown. Only microcystins, one class of cyanopeptides, have
          been studied intensively and the wealth of evidence regarding exposure conc
         entrations and toxicity led to their inclusion in risk management frameworks
          for water quality. However, cyanobacteria produce an incredible diversity o
         f hundreds of cyanopeptides beyond the class of microcystins. The question a
         rises, whether the other cyanopeptides are in fact of no human and ecologica
         l concern or whether these compounds merely received (too) little attention
         thus far. Current observations suggest that an assessment of their (eco)toxi
         cological risk is indeed relevant: First, other cyanopeptides, including cya
         nopeptolins and anabaenopeptins, can occur just as frequently and at similar
          nanomolar concentrations as microcystins in surface waters. Second, cyanope
         ptolins, anabaenopeptins, aeruginosins and microginins inhibit proteases in
         the nanomolar range, in contrast to protein phosphatase inhibition by microc
         ystins. Cyanopeptolins, aeruginosins, and aerucyclamide also show toxicity a
         gainst grazers in the micromolar range comparable to microcystins. The key c
         hallenge for a comprehensive risk assessment of cyanopeptides remains their
         large structural diversity, lack of reference standards, and high analytical
          requirements for identification and quantification. One way forward would b
         e a prevalence study to identify the priority candidates of tentatively abun
         dant, persistent, and toxic cyanopeptides to make comprehensive risk assessm
         ents more manageable.
' (1693 chars) serialnumber => protected'0043-1354' (9 chars) doi => protected'10.1016/j.watres.2018.12.048' (28 chars) uid => protected18207 (integer) _localizedUid => protected18207 (integer)modified _languageUid => protectedNULL _versionedUid => protected18207 (integer)modified pid => protected124 (integer)
8 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=23610, pid=124) originalId => protected23610 (integer) authors => protected'Kakouei,&nbsp;K.; Kraemer,&nbsp;B.&nbsp;M.; Anneville,&nbsp;O.; Carvalho,&nb
         sp;L.; Feuchtmayr,&nbsp;H.; Graham,&nbsp;J.&nbsp;L.; Higgins,&nbsp;S.; Pomat
         i,&nbsp;F.; Rudstam,&nbsp;L.&nbsp;G.; Stockwell,&nbsp;J.&nbsp;D.; Thackeray,
         &nbsp;S.&nbsp;J.; Vanni,&nbsp;M.&nbsp;J.; Adrian,&nbsp;R.
' (285 chars) title => protected'Phytoplankton and cyanobacteria abundances in mid-21st century lakes depend
         strongly on future land use and climate projections
' (127 chars) journal => protected'Global Change Biology' (21 chars) year => protected2021 (integer) volume => protected27 (integer) issue => protected'24' (2 chars) startpage => protected'6409' (4 chars) otherpage => protected'6422' (4 chars) categories => protected'climate change; forecast; freshwater lakes; land use change; machine learnin
         g; phytoplankton; cyanobacteria
' (107 chars) description => protected'Land use and climate change are anticipated to affect phytoplankton of lakes
          worldwide. The effects will depend on the magnitude of projected land use a
         nd climate changes and lake sensitivity to these factors. We used random for
         ests fit with long-term (1971–2016) phytoplankton and cyanobacteria abunda
         nce time series, climate observations (1971–2016), and upstream catchment
         land use (global Clumondo models for the year 2000) data from 14 European an
         d 15 North American lakes basins. We projected future phytoplankton and cya
         nobacteria abundance in the 29 focal lake basins and 1567 lakes across foca
         l regions based on three land use (sustainability, middle of the road, and r
         egional rivalry) and two climate (RCP 2.6 and 8.5) scenarios to mid-21st cen
         tury. On average, lakes are expected to have higher phytoplankton and cyanob
         acteria due to increases in both urban land use and temperature, and decreas
         es in forest habitat. However, the relative importance of land use and clima
         te effects varied substantially among regions and lakes. Accounting for land
          use and climate changes in a combined way based on extensive data allowed u
         s to identify urbanization as the major driver of phytoplankton development
         in lakes located in urban areas, and climate as major driver in lakes locate
         d in remote areas where past and future land use changes were minimal. For a
         pproximately one-third of the studied lakes, both drivers were relatively im
         portant. The results of this large scale study suggest the best approaches f
         or mitigating the effects of human activity on lake phytoplankton and cyanob
         acteria will depend strongly on lake sensitivity to long-term change and the
          magnitude of projected land use and climate changes at a given location. Ou
         r quantitative analyses suggest local management measures should focus on re
         taining nutrients in urban landscapes to prevent nutrient pollution from exa
         cerbating ongoing changes to lake ecosystems from climate change.
' (1965 chars) serialnumber => protected'1354-1013' (9 chars) doi => protected'10.1111/gcb.15866' (17 chars) uid => protected23610 (integer) _localizedUid => protected23610 (integer)modified _languageUid => protectedNULL _versionedUid => protected23610 (integer)modified pid => protected124 (integer)
Jones, M. R.; Pinto, E.; Torres, M. A.; Dörr, F.; Mazur-Marzec, H.; Szubert, K.; Tartaglione, L.; Dell'Aversano, C.; Miles, C. O.; Beach, D. G.; McCarron, P.; Sivonen, K.; Fewer, D. P.; Jokela, J.; Janssen, E. M. -L. (2021) CyanoMetDB, a comprehensive public database of secondary metabolites from cyanobacteria, Water Research, 196, 117017 (12 pp.), doi:10.1016/j.watres.2021.117017, Institutional Repository
Pittino, F.; Fink, S.; Oliveira, J.; Janssen, E. M. L.; Scheidegger, C. (2024) Lithic bacterial communities: ecological aspects focusing on Tintenstrich communities, Frontiers in Microbiology, 15, 1430059 (12 pp.), doi:10.3389/fmicb.2024.1430059, Institutional Repository
Rougé, V.; von Gunten, U.; Janssen, E. M. L. (2024) Reactivity of cyanobacteria metabolites with ozone: multicompound competition kinetics, Environmental Science and Technology, 58(26), 11802-11811, doi:10.1021/acs.est.4c02242, Institutional Repository
Torres, M. de A.; Dax, A.; Grand, I.; vom Berg, C.; Pinto, E.; Janssen, E. M..L. (2024) Lethal and behavioral effects of semi-purified microcystins, Micropeptin and apolar compounds from cyanobacteria on freshwater microcrustacean Thamnocephalus platyurus, Aquatic Toxicology, 273, 106983 (9 pp.), doi:10.1016/j.aquatox.2024.106983, Institutional Repository
de Almeida Torres, M.; Jones, M. R.; vom Berg, C.; Pinto, E.; Janssen, E. M. -L. (2023) Lethal and sublethal effects towards zebrafish larvae of microcystins and other cyanopeptides produced by cyanobacteria, Aquatic Toxicology, 263, 106689 (11 pp.), doi:10.1016/j.aquatox.2023.106689, Institutional Repository
Wang, X.; Wullschleger, S.; Jones, M.; Reyes, M.; Bossart, R.; Pomati, F.; Janssen, E. M. -L. (2024) Tracking extensive portfolio of cyanotoxins in five-year lake survey and identifying indicator metabolites of cyanobacterial taxa, Environmental Science and Technology, 58(37), 16560-16569, doi:10.1021/acs.est.4c04813, Institutional Repository
Eyring, S.; Reyes, M.; Merz, E.; Baity-Jesi, M.; Ntetsika, P.; Ebi, C.; Dennis, S.; Pomati, F. (2025) Five years of high-frequency data of phytoplankton zooplankton and limnology from a temperate eutrophic lake, Scientific Data, 12(1), 653 (13 pp.), doi:10.1038/s41597-025-04988-9, Institutional Repository
Janssen, E. M. -L. (2019) Cyanobacterial peptides beyond microcystins – a review on co-occurrence, toxicity, and challenges for risk assessment, Water Research, 151, 488-499, doi:10.1016/j.watres.2018.12.048, Institutional Repository
Kakouei, K.; Kraemer, B. M.; Anneville, O.; Carvalho, L.; Feuchtmayr, H.; Graham, J. L.; Higgins, S.; Pomati, F.; Rudstam, L. G.; Stockwell, J. D.; Thackeray, S. J.; Vanni, M. J.; Adrian, R. (2021) Phytoplankton and cyanobacteria abundances in mid-21st century lakes depend strongly on future land use and climate projections, Global Change Biology, 27(24), 6409-6422, doi:10.1111/gcb.15866, Institutional Repository

Photo de couverture: Bloom ou prolifération de cyanobactéries pélagiques Microcystis sp., lac de Constance (Amt für Wasser und Energie, Saint-Gall, Lukas Taxböck)