Cyanobacterial Toxic and Bioactive Peptides in Freshwater Bodies of Greece: Concentrations, Occurrence Patterns, and Implications for Human Health.

Spyros Gkelis,Thomas Lanaras,Kaarina Sivonen

doi:10.3390/md13106319

Spyros Gkelis, Thomas Lanaras + Show 1 more

Open Access

https://doi.org/10.3390/md13106319

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Abstract

Cyanobacterial harmful algal blooms represent one of the most conspicuous waterborne microbial hazards in aquatic environments mostly due to the production of toxic secondary metabolites, mainly microcystins (MCs). Other bioactive peptides are frequently found in cyanobacterial blooms, yet their concentration and ecological relevance is still unknown. In this paper we studied the presence and concentration of cyanobacterial peptides (microcystins, anabaenopeptins, anabaenopeptilides) in 36 Greek freshwater bodies, using HPLC-DAD, ELISA, and PP1IA. Microcystins were found in more than 90% of the samples investigated, indicating that microcystin-producing strains seem to also occur in lakes without blooms. Microcystins MC-RR, MC-LR, and MC-YR were the main toxin constituents of the bloom samples. Anabaenopeptin A and B were predominant in some samples, whereas anabaenopeptolide 90A was the only peptide found in Lake Mikri Prespa. The intracellular concentrations of anabaenopeptins produced by cyanobacterial bloom populations are determined for the first time in this study; the high (>1000 µg·L−1) anabaenopeptin concentration found indicates there may be some impacts, at least on the ecology and the food web structure of the aquatic ecosystems. The maximum intracellular MC values measured in Lakes Kastoria and Pamvotis, exceeding 10,000 µg·L−1, are among the highest reported.

Highlights

Cyanobacterial Harmful Algal Blooms represent one of the most conspicuous waterborne microbial hazards to human and agricultural water supplies, fisheries production, and freshwater and marine ecosystems [1]
During the past 20 years, many other bioactive peptide groups have been discovered in cyanobacteria, such as aeruginosins, microginins, cyanopeptolins, anabaenopeptins, anabaenopeptilides, microviridins, and nostophycins; to date, more than 600 cyanobacterial peptides have been described
Of the freshwaters sampled once contain microcystin(s) shows that microcystin-producing strains seem to occur in lakes without blooms, as previously observed [20]

Summary

Introduction

Cyanobacterial Harmful Algal Blooms (or CyanoHABs) represent one of the most conspicuous waterborne microbial hazards to human and agricultural water supplies, fisheries production, and freshwater and marine ecosystems [1]. This hazard results from the production of cyanotoxins, harmful secondary metabolites such as microcystins (MCs), saxitoxins, and cylindrospermopsins that can have deleterious effects within reservoirs and in downstream receiving water systems during releases [2]. The continuous and rising interest stems both from the surveillance of aquatic systems, especially where toxic compounds are raising concerns of public health, and from various and diverse bioactivities of unique structures with potential pharmacological implications [7] These peptides are frequently found in cyanobacterial blooms, along with numerous other not-yet-identified peptides [8,9,10]

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Discussion

Conclusion