Toxicity at the edge of life: A review on cyanobacterial toxins from extreme environments

Cyanotoxins are secondary metabolites produced by cyanobacteria, of varied chemical nature and toxic effects. Although cyanobacteria thrive in all kinds of ecosystems on Earth even under very harsh conditions, current knowledge on cyanotoxin distribution is almost restricted to freshwaters from temp...

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Bibliographic Details
Published in:Marine Drugs
Main Authors: Cires Gómez, Samuel, Casero, María Cristina, Quesada del Corral, Antonio
Other Authors: UAM. Departamento de Biología
Format: Article in Journal/Newspaper
Language:English
Published: MDPI 2024
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Online Access:http://hdl.handle.net/10486/713254
https://doi.org/10.3390/md15070233
Description
Summary:Cyanotoxins are secondary metabolites produced by cyanobacteria, of varied chemical nature and toxic effects. Although cyanobacteria thrive in all kinds of ecosystems on Earth even under very harsh conditions, current knowledge on cyanotoxin distribution is almost restricted to freshwaters from temperate latitudes. In this review, we bring to the forefront the presence of cyanotoxins in extreme environments. Cyanotoxins have been reported especially in polar deserts (both from the Arctic and Antarctica) and alkaline lakes, but also in hot deserts, hypersaline environments, and hot springs. Cyanotoxins detected in these ecosystems include neurotoxins—anatoxin-a, anatoxin-a (S), paralytic shellfish toxins, -methylaminopropionic acid, N-(2-aminoethyl) glycine and 2,4-diaminobutyric acid- and hepatotoxins –cylindrospermopsins, microcystins and nodularins—with microcystins being the most frequently reported. Toxin production there has been linked to at least eleven cyanobacterial genera yet only three of these (Arthrospira, Synechococcus and Oscillatoria) have been confirmed as producers in culture. Beyond a comprehensive analysis of cyanotoxin presence in each of the extreme environments, this review also identifies the main knowledge gaps to overcome (e.g., scarcity of isolates and –omics data, among others) toward an initial assessment of ecological and human health risks in these amazing ecosystems developing at the very edge of life María Cristina Casero was funded by the Spanish PhD research fellowship (BES-2014-069106) awarded by the Spanish Ministry of Economy and Competitiveness. We would like to thank the two anonymous reviewers for offering constructive comments on an earlier version of this manuscript.