CyanoTRACKER: A cloud-based integrated multi-platform architecture for global observation of cyanobacterial harmful algal blooms

ABSTRACTLittle is known about the molecular and physiological function of co-occurring microbes within freshwater cyanobacterial harmful algal blooms (cHABs). To address this, community metatranscriptomes collected from the western basin of Lake Erie during August 2012 were examined. Using sequence data, we tested the hypothesis that the activity of the microbial community members is independent of community structure. Predicted metabolic and physiological functional profiles from spatially distinct metatranscriptomes were determined to be ≥90% similar between sites. Targeted analysis ofMicrocystis aeruginosa, the historical causative agent of cyanobacterial harmful algal blooms over the past ∼20 years, as well as analysis ofPlanktothrix agardhiiandAnabaena cylindrica, revealed ongoing transcription of genes involved in microcystin toxin synthesis as well as the acquisition of both nitrogen and phosphorus, nutrients often implicated as independent bottom-up drivers of eutrophication in aquatic systems. Transcription of genes involved in carbon dioxide (CO2) concentration and metabolism also provided support for the alternate hypothesis that high-pH conditions and dense algal biomass result in CO2-limiting conditions that further favor cyanobacterial dominance. Additionally, the presence ofMicrocystis-specific cyanophage sequences provided preliminary evidence of possible top-down virus-mediated control of cHAB populations. Overall, these data provide insight into the complex series of constraints associated withMicrocystisblooms that dominate the western basin of Lake Erie during summer months, demonstrating that multiple environmental factors work to shape the microbial community.

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Global health concern of cyanotoxins in surface water and its various detection methods

Current Botany ◽

10.25081/cb.2020.v11.6059 ◽

2020 ◽

pp. 65-74

Author(s):

M. Ramya ◽

A. Umamaheswari ◽

S. Elumalai

Keyword(s):

Harmful Algal Blooms ◽

Algal Blooms ◽

Biological Properties ◽

Detection Methods ◽

Health Concern ◽

Polluted Water ◽

Blue Green Algae ◽

Treatment Techniques ◽

Route Of Exposure ◽

Cyanobacterial Harmful Algal Blooms

Water is an absolutely required resource for life nourishment especially for the purpose of drinking, domestic and farming. People in various part of the world are under prodigious threat due to unenviable changes in the physical-chemical and biological properties of an ecosystem. Due to anthropogenic causes like industrialization, the use of fertilizers and urbanization leads to highly polluted water bodies that include fresh and brackish water. These changes influence the harmful growth of cyanobacteria that is blue green algae. cyanoHABs (Cyanobacterial Harmful Algal Blooms) became a worldwide threat to drinking and recreational purpose due to its adopting nature according to the temperature fluctuations. In this study, a basic introduction to cyanotoxins as well as the entanglement of public health that includes route of exposure health effects and the pervasive impact of cyanotoxins and alleviation efforts in the waterbodies along with that the toxicosis. Cyanobacterial toxins such as hepatotoxicosis, neurotoxicosis, gastrointestinal disturbances respiratory and allergic reactions were reviewed. Their detection process and the treatment techniques with various physicochemical methods and bioassay methods were also reviewed.

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Cyanopeptides Restriction and Degradation Co-mediate Microbiota Assembly During a Freshwater Cyanobacterial Harmful Algal Bloom (CyanoHAB)

10.1101/2021.12.31.474673 ◽

2022 ◽

Author(s):

Han Gao ◽

Ze Zhao ◽

Lu Zhang ◽

Feng Ju

Keyword(s):

Community Assembly ◽

Harmful Algal Blooms ◽

Algal Blooms ◽

Algal Bloom ◽

Lake Taihu ◽

Harmful Algal Bloom ◽

Size Fraction ◽

Freshwater Ecosystems ◽

Cyanobacterial Harmful Algal Blooms ◽

Microbiota Diversity

Cyanobacterial harmful algal blooms (CyanoHABs) are globally intensifying and exacerbated by climate change and eutrophication. However, microbiota assembly mechanisms underlying CyanoHABs remain scenario specific and elusive. Especially, cyanopeptides, as a group of bioactive secondary metabolites of cyanobacteria, could affect microbiota assembly and ecosystem function. Here, the trajectory of cyanopeptides were followed and linked to microbiota during Microcystis-dominated CyanoHABs in lake Taihu, China. The most abundant cyanopeptide classes detected included microginin, spumigin, microcystin, nodularin and cyanopeptolin with total MC-LR-equivalent concentrations between 0.23 and 2051.54 ppb, of which cyanotoxins beyond microcystins (e.g., cyanostatin B and nodularin_R etc.) far exceeded reported organismal IC50 and negatively correlated with microbiota diversity, exerting potential collective eco-toxicities stronger than microcystins alone. The microbial communities were differentiated by size fraction and sampling date throughout CyanoHABs, and surprisingly, their variances were better explained by cyanopeptides (19-38%) than nutrients (0-16%). Cyanopeptides restriction (e.g., inhibition) and degradation are first quantitatively verified as the deterministic drivers governing community assembly, with stochastic processes being mediated by interplay between cyanopeptide dynamics and lake microbiota. This study presents an emerging paradigm in which cyanopeptides restriction and degradation co-mediate lake water microbiota assembly, unveiling new insights about the ecotoxicological significance of CyanoHABs to freshwater ecosystems.

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