Insight into Unprecedented Diversity of Cyanopeptides in Eutrophic Ponds Using an MS/MS Networking Approach

Abstract

Man-made shallow fishponds in the Czech Republic have been facing high eutrophication since the 1950s. Anthropogenic eutrophication and feeding of fish have strongly affected the physicochemical properties of water and its aquatic community composition, leading to harmful algal bloom formation. In our current study, we characterized the phytoplankton community across three eutrophic ponds to assess the phytoplankton dynamics during the vegetation season. We microscopically identified and quantified 29 cyanobacterial taxa comprising non-toxigenic and toxigenic species. Further, a detailed cyanopeptides (CNPs) profiling was performed using molecular networking analysis of liquid chromatography-tandem mass spectrometry (LC-MS/MS) data coupled with a dereplication strategy. This MS networking approach, coupled with dereplication, on the online global natural product social networking (GNPS) web platform led us to putatively identify forty CNPs: fourteen anabaenopeptins, ten microcystins, five cyanopeptolins, six microginins, two cyanobactins, a dipeptide radiosumin, a cyclooctapeptide planktocyclin, and epidolastatin 12. We applied the binary logistic regression to estimate the CNPs producers by correlating the GNPS data with the species abundance. The usage of the GNPS web platform proved a valuable approach for the rapid and simultaneous detection of a large number of peptides and rapid risk assessments for harmful blooms.

New Micropeptins with Anti-Neuroinflammatory Activity Isolated from a Cyanobacterial Bloom

“…Comparing the precursor m / z values and previous molecular networks available in the literature, we putatively identified the metabolites in clusters 1 and 2 as micropeptins or cyanopeptolins. 14 , 15 Node 1019 and 1005 showed high ion counts in mass spectrometry analysis and were abundant in the high-performance liquid chromatography (HPLC) profile, and these metabolites were targeted for isolation (cf. Figures 2 , S4, and S5 ).…”

Algal Toxic Compounds and Their Aeroterrestrial, Airborne and other Extremophilic Producers with Attention to Soil and Plant Contamination: A Review

“…However, cyanoprokaryotes can produce also some different from “standard” cyanotoxins alkaloids (e.g., nostodione—Nd) and specific cyanopeptides (CNPs), including NRPs, polyketides (PKs) and their hybrids (NRPs/PKs) [ 59 , 60 ]. Some of them are common in different cyanoprokaryote genera (e.g., anabaenopeptins—Aps, cyanopeptolins—CPs), while others are specific to a single genus (e.g., oscillatorin in Planktothrix ( Oscillatoria ) [ 61 ] and cryptophycins—Crs in Nostoc ) [ 59 ].…”

First Report on Microcystis as a Potential Microviridin Producer in Bulgarian Waterbodies

“…However, since the beginning of the 21st century, a series of studies have demonstrated that the assessment of cyanobacterial toxicity cannot solely rely on the commonly known cyanotoxins, implying the activity of other compounds, the structure and function of which need elucidation (for details see [ 4 ]). In this regard, beyond the best studied and routinely monitored cyanotoxins from the specific group of cyclic non-ribosomally produced heptapeptides, named microcystins [ 1 , 2 , 3 ], more than six hundred other peptides or peptidic metabolites, commonly unified as cyanopeptins (CNPs), were isolated from the vast metabolite repertory of cyanoprokaryotes [ 5 , 6 , 7 , 8 ]. Despite some variations in composition and amounts, these CNPs were regularly found during CyanoHABs [ 7 ].…”