Eukaryotic Sequences in the 16SrRNA Metagenomic Dataset of Algal–bacterial Consortia of the White Sea Coastal Zone

Abstract

The libraries of bacterial 16SrRNA gene fragment from algal–bacterial consortia of the White Sea coastal zone are analyzed. Up to 3% of the reads have revealed to correspond to eukaryotic rRNA. They related to following main eukaryotic clades: Discoba, Stramenopiles, Ciliata, Amoebozoa, and Nucletmycea. Amoebae, especially Vermamoeba, were present in all samples. In one sample, heterolobose amoeba Paravahlkampfia was detected. These microorganisms are parasites of microalgae, which can induce significant damage to industrial cultures. However, the data on their physiology and distribution are scarce. This study provides new evidence about the diversity of herbivorous eukaryotic microorganisms in natural algal‐containing consortia.

Formation of the phosphate-resistant communities of microalgae and bacteria in the subpolar waters

“…Environmental DNA was isolated using a MagJET Plant Genomic DNA Kit (Thermo Fisher Scientific, USA); bacteria were identified by metabarcoding based on the V4 hypervariable fragment of the gene of 16S rRNA; 16S rRNA libraries preparation, sequencing, and metagenomic data analysis were conducted according to Kublanovskaya et al (2020). For the description of eukaryotic components a previously described approach was used (Chekanov et al, 2019). Fragments of the samples were seeded into BG-11 (Stanier et al, 1971) media with increased content of phosphates (160 mg(P)/L).…”

Grazing preferences of three species of amoebae on cyanobacteria and green algae

“…Suggested mechanisms for bloom decline include environmental changes such as water body stratification or mixing (Knapp et al, 2021), cyanophages (McKindles et al, 2021), fungal pathogens (Han et al, 2020;Weisbrod et al, 2020), allelopathy (Chia et al, 2018) and grazing by various types of zooplankton and protists (Daft et al, 1985). Both ciliates (Canter et al, 1990;Takamura & Yasuno, 1983) and amoebae (Haberey, 1973;Van Wichelen et al, 2010;Wright et al, 1981;Yamamoto, 1981) may consume certain cyanobacterial species, and blooms of the cyanobacterium Microcystis have been described as a "diversity hotspot" for amoebae (Van Wichelen, D'Hondt, et al, 2016;Van Wichelen, Vanormelingen, et al, 2016).…”

The Dynamics of the Bacterial Community of the Photobioreactor-Cultivated Green Microalga Haematococcus lacustris during Stress-Induced Astaxanthin Accumulation

“…The close coexistence of the microalga and other microorganisms raises two questions: (i) how broad their diversity is and (ii) how they interact with the microalga.Despite the importance of this issue, little is known about the microorganisms existing in H. lacustris monoalgal cultures except for a few reports on the parasitic micromycetes damaging industrial algal cultures [23]; the blastoclad Paraphysoderma specifically interacts with H. lacustris cells attacking it on a certain stage of its lifecycle [24]. Previously, we described natural microbial communities formed around H. lacustris from the White Sea coastal rock baths [25][26][27]. As with H. lacustris itself, many microorganisms from these communities are characterized by their resilience to adverse environmental conditions.…”

“…Cyanobacteria and H. lacustris are dominant photosynthetic organisms in these biotopes [25,26]. Natural algal communities might also include grazing protists, e.g., Vermamoeba, Paravahlkampfia, ciliates [27]. The prokaryotes common for H. lacustris-based natural communities from the White Sea are dominated by Comamonadaceae and also include representatives of the families Cytophagaceae, Xanthomonadaceae, Acetobacteraceae, Rhodobacteraceae and Rhodocyclaceae [26].…”