Distribution of toxigenic cyanobacteria in Alpine lakes and rivers as revealed by molecular screening : research data underlying the article

Jablonska, Maša (author), Cerasino, Leonardo (author), Boscaini, Adriano (author), Capelli, Camilla (author), Greco, Claudia (author), Krivograd-Klemenčič, Aleksandra (author), Mischke, Ute (author), Salmaso, Nico (author), Kurmayer, Rainer (author)

The increasing frequency of cyanobacteria blooms in waterbodies caused by ecosystem eutrophication could endanger human health. This risk can be mitigated by effective monitoring incorporating molecular methods. To date, most molecular studies on toxigenic cyanobacteria have been limited to microcystins (MCs), disregarding other cyanotoxins, to freshwater planktic habitats while ignoring benthic habitats, and to limited geographic areas (usually one or a few specific waterbodies). In this study, we used PCR-based methods including PCR product sequencing and chemical-analytical methods (LC-MS/MS) to screen many plankton (n = 123) and biofilm samples (n = 113) originating from 29 Alpine lakes and 18 rivers for their cyanotoxin production potential. Both mcyE (indicating MC synthesis) and anaC (indicating anatoxin (ATX) synthesis) gene fragments were able to qualitatively predict MC or ATX occurrence. The abundance of mcyE gene fragments was significantly related to MC concentrations in plankton samples (R2 = 0.61). mcyE gene fragments indicative of MC synthesis were most abundant in planktic samples (65 %) and were assigned to the genera Planktothrix and Microcystis. However, mcyE rarely occurred in biofilms of lakes and rivers, i.e., 4 % and 5 %, respectively, and were assigned to Microcystis, Planktothrix, and Nostoc. In contrast, anaC gene fragments occurred frequently in planktic samples (14 % assigned to Tychonema, Phormidium (Microcoleus), and Oscillatoria), but also in biofilms of lakes (49 %) and rivers (18 %) and were assigned to the genera Phormidium, Oscillatoria, and Nostocales. The cyrJ gene fragment indicating cylindrospermopsin synthesis occurred only once in plankton (assigned to Dolichospermum), while saxitoxin synthesis potential was not detected. For plankton samples, monomictic and less eutrophic conditions were positively related to mcyE/MC occurrence frequency, while oligomictic conditions were related to anaC/ATX frequency. The anaC/ATX frequency in biofilm was related to the lake habitats generally showing higher biodiversity as revealed from metabarcoding in a parallel study.

• Language: English
• Keywords: European Alps, cyanotoxins, cyanobacteria, planktic habitats, benthic habitats, water quality monitoring, early warning, qPCR, PCR, LC-MS/MS, DNA sequencing
• Typology: 2.20 - Complete scientific database of research data
• Geographic coverage: Mondsee, Austria, and/in Ljubljana, Slovenia
• Time coverage: From/Od 2021-01-11 to/do 2023-06-23
• Organization: BF - Biotechnical Faculty
• Year: 2026
• PID: 20.500.12556/RUL-182463
• Publication date in RUL: 18.05.2026
• Collection: This document is a collection and includes 1 document.

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Applies to: research data underlying the article

Secondary language

• Language: Slovenian
• Title: Porazdelitev toksigenih cianobakterij v alpskih jezerih in rekah na podlagi molekularnega pregleda : raziskovalni podatki, obravnavani v članku

Abstract

Vse pogostejše množične razrasti cianobakterij v vodnih telesih, ki jih povzroča evtrofikacija ekosistemov, bi lahko ogrozile zdravje ljudi. To tveganje je mogoče zmanjšati z učinkovitim spremljanjem, ki vključuje molekularne metode. Do danes je bila večina molekularnih raziskav toksigenih cianobakterij omejena na mikrocistine (MC) v planktonskih habitatih celinskih voda in na omejena geografska območja (običajno eno ali nekaj izbranih vodnih teles). Drugi cianotoksini in bentoški habitati so bili pogosto spregledani. V tej raziskavi smo uporabili metode, ki temeljijo na PCR, vključno s sekvenciranjem produktov PCR, in kemijsko-analitske metode (LC-MS/MS), da smo pregledali potencial za proizvodnjo cianotoksinov v številnih vzorcih planktona (n = 123) in bentosa (n = 113) iz 29 alpskih jezer in 18 rek. Odseki tarčnih genov mcyE (ki je odgovoren za proizvodnjo MC) in anaC (ki je odgovoren za proizvodnjo anatoksina [ATX]) so lahko kvalitativno napovedali prisotnost MC ali ATX. Številčnost gena mcyE je bila statistično značilno povezana s koncentracijo MC v vzorcih planktona (R2 = 0,61). Geni mcyE, ki nakazujejo sintezo MC, so bili najbolj razširjeni v vzorcih planktona (65 %) in so bili uvrščeni v rodova Planktothrix in Microcystis. Nasprotno pa so se geni mcyE redko pojavili v vzorcih bentosa iz jezer (4 %) in rek (5 %), kjer so bili uvrščeni v rodove Microcystis, Planktothrix in Nostoc. Po drugi strani pa so se geni anaC pogosto pojavljali v vzorcih planktona (14 %), uvrščeni v rodove Tychonema, Phormidium (Microcoleus) in Oscillatoria, pa tudi v bentosu jezer (49 %) in rek (18 %), uvrščeni v rodove Phormidium, Oscillatoria in Nostocales. Gen cyrJ, ki nakazuje sintezo cilindrospermopsinov, se je v planktonu pojavil le enkrat (uvrščen v rod Dolichospermum), potencial za sintezo saksitoksinov pa ni bil opažen v nobenem vzorcu. Pri vzorcih planktona je bila pogostost mcyE in MC v pozitivni korelaciji z monomiktičnimi in manj evtrofnimi razmerami, medtem ko je bila pogostost anaC in ATX v pozitivni korelaciji z oligomiktičnimi razmerami. Pogostost anaC in ATX v bentosu je bila povezana z vzorci iz jezerskih habitatov, v katerih rezultati metabarkodiranja iz vzporedne raziskave na splošno kažejo večjo biotsko raznovrstnost kot vzorci iz rečnih habitatov.

• Keywords: alpska regija, cianotoksini, cianobakterije, planktonski habitati, bentoški habitati, monitoring voda, zgodnje zaznavanje, qPCR, PCR, LC-MS/MS, sekvenciranje DNA