Complete genomes derived by directly sequencing freshwater bloom populations emphasize the significance of the genus level ADA clade within the Nostocales

Dreher, Theo W.; Davis, Edward W.; Mueller, Robert F.

doi:10.1016/j.hal.2021.102005

Cited by 16 publications

(7 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…were detected at S13 (upper Makhambet) sampling point (Figure 4 and Table 3). This is in line with other studies, which found that the ADAclade is a highly significant component of cyanobacterial HABs (Dreher et al, 2021), and dominant microcystin producer is not necessarily the predominant cyanobacterial species in the water stream (Dadheech et al, 2014;Lee et al, 2015;Scherer et al, 2017). In summary, our study demonstrates that potentially toxic cyanobacteria including toxigenic strains widely distributed in Ural River waters.…”

Section: Discussionsupporting

confidence: 92%

Combining Imaging Flow Cytometry and Molecular Biological Methods to Reveal Presence of Potentially Toxic Algae at the Ural River in Kazakhstan

et al. 2021

View full text Add to dashboard Cite

Algal blooms occur in freshwater bodies throughout the world, often leading to fish kills. Cases of these kills along the Ural River were reported in 2018–2019, involving significant amount of sturgeon in fish farming areas. In this study, the analysis of algal samples from the delta of the Ural River up to 100 km inland was carried out from August to December 2019 using imaging flow cytometry (IFC), molecular biological, and microscopic techniques. We identified the filamentous cyanobacteria Cuspidothrix issatschenkoi, Dolichospermum cf. flos-aquae, Dolichospermum cf. macrosporum, Pseudanabaena limnetica, and Planktothrix spp. as the dominant potentially toxic phytoplankton species, and we also found minor quantities of Cylindrospermopsis raciborskii. For the first time, molecular phylogenetic investigations of field clones of cyanobacteria from Ural River were carried out to establish the taxa of the dominant species and to identify the presence of genes encoding toxins. The complementary analysis with nanopore-based next-generation sequencing overlapped with the results of IFC and was instrumental in revealing minor cyanobacteria taxa. Real-time PCR analysis and sequencing indicated the presence of Microcystis and ADA-clade spp. as well as genes associated with the production of microcystin (mcyE) and the algal neurotoxin saxitoxin (sxtA) originating from cyanobacteria. These findings suggest that toxin-producing cyanobacteria could become a threat in the Ural River near Atyrau, which can significantly affect aquaculture in the region.

show abstract

Section: Discussionsupporting

confidence: 92%

Combining Imaging Flow Cytometry and Molecular Biological Methods to Reveal Presence of Potentially Toxic Algae at the Ural River in Kazakhstan

et al. 2021

View full text Add to dashboard Cite

show abstract

“…The synteny of the CYN gene cluster was the same as previously described for Aphanizomenon sp. 10E6 (Dreher et al, 2021; Stücken & Jakobsen, 2010), except for missing cyr K. U. natans strain TAC611 contained sequences for cyr G and cyr J, while U. natans Ak1311 did not contain any CYN genes.…”

Section: Resultsmentioning

confidence: 99%

“…Both the phylogenomic and phylogenetic analyses used in this study yielded congruent results supporting the unification of Chrysosporum ovalisporum and Umezakia natans . Taxonomic thresholds based on ANI (a measure of nucleotide‐level genomic similarity between genomes) suggest a species boundary at ANI 95–96% (Ahn et al, 2017; Johansen et al, 2021; Willis & Woodhouse, 2020), and genus boundary occurring <94 ANI (Ahn et al, 2017), which in practice appears ~85–90 ANI (Dreher et al, 2021) and corresponds to 94.8% ± 0.25 16S rRNA identity as proposed by Yarza et al (2014). The ANI of the strains previously known as U. natans and C. ovalisporum demonstrated high genome similarity between strains (ANI of >99.5 and AF > 0.9) and genus‐level separation from C. bergii (83 ANI between clusters).…”

Section: Discussionmentioning

confidence: 99%

Chrysosporum ovalisporum is synonymous with the true‐branching cyanobacterium Umezakia natans (Nostocales/Aphanizomenonaceae)

McGregor

Sendall

Niiyama

et al. 2023

Journal of Phycology

View full text Add to dashboard Cite

True branching is a facultative characteristic only known from two cyanobacteria in the Aphanizomenonaceae, Umezakia natans and Dolichospermum brachiatum. In both cases, its expression has been associated with environmental stress, and its practical use as a diacritical feature has been previously evaluated. In this study, we undertook further evaluation of the phylogeny of Umezakia natans and its relationship to Chrysosporum ovalisporum as a previous study suggested the two were potentially congeneric. We used combined morphological, phylogenetic, and phylogenomic approaches to determine their relatedness using new strains available from a broad geographic range. Phylogenetic analysis based on 16S rRNA gene sequences showed that Australian C. ovalisporum and Japanese U. natans strains clustered together with accessions of C. ovalisporum originating from Australia, Israel, and Spain, with high p-distance similarity values (99.5%-99.9%). Additionally, differences between the two species in the 16S-23S ITS region was low (0%-2.5%). The average nucleotide identity of the U. natans and C. ovalisporum strains was also high (ANI of > 99.5 and AF > 0.9) and supported a genus-level separation from Chrysosporum bergii (83 ANI between clusters). Furthermore, in culture, strains of both species grown in vitamin-free media showed facultative true branching, a feature not previously known in C. ovalisporum. Collectively, the results support unification of C. ovalisporum and U. natans according to the principle of priority as Umezakia ovalisporum.

show abstract

“…16S rRNA-based phylogenies are so far unable to resolve Aphanizomenon and Anabaena/Dolichospermum 57 . For example, addition of metagenomic data (with morphological validation) from 16 Aphanizomenon, Anabaena, and Dolichospermum strains collected in the Paci c northwest of the United States to collections of Cyanobacterial genomes from previous phylogenetic analyses still placed some strains, such as an Anabaena strain collected from Washington state, within Aphanizomenon clades 58 .…”

Section: Resultsmentioning

confidence: 99%

The volatilome reveals microcystin concentration, microbial composition, and oxidative stress in a critical Oregon freshwater lake

Collart¹,

Jiang²,

Halsey

2023

Preprint

View full text Add to dashboard Cite

Toxins commonly produced by cyanobacterial blooms in freshwater lakes are a serious public health problem. The conditions leading to toxin production are currently unpredictable, thereby requiring expensive sampling and monitoring programs globally. We explored the potential of volatile organic compounds (VOCs) to indicate microcystin presence and concentration, and microbial community composition in Upper Klamath Lake, OR. Elastic net regularization regression selected 29 of 229 detected m/z+1 values (corresponding to unique VOCs) in models predicting microcystin toxicity that outperformed or significantly improved upon regression models based on environmental parameters, including chlorophyll, pH, and temperature. Several m/z+1 values selected by elastic net were putatively identified as saturated fatty aldehydes (SFAs), which are important in defending cyanobacteria against oxidative stress. Unique sets of m/z+1 values were also identified by elastic net regression that predicted the relative abundance of the most dominant bacterial phyla, classes, and cyanobacterial genera. These results show that VOCs may be a key component of lake monitoring strategies.

show abstract

Complete genomes derived by directly sequencing freshwater bloom populations emphasize the significance of the genus level ADA clade within the Nostocales

Cited by 16 publications

References 47 publications

Combining Imaging Flow Cytometry and Molecular Biological Methods to Reveal Presence of Potentially Toxic Algae at the Ural River in Kazakhstan

Combining Imaging Flow Cytometry and Molecular Biological Methods to Reveal Presence of Potentially Toxic Algae at the Ural River in Kazakhstan

Chrysosporum ovalisporum is synonymous with the true‐branching cyanobacterium Umezakia natans (Nostocales/Aphanizomenonaceae)

The volatilome reveals microcystin concentration, microbial composition, and oxidative stress in a critical Oregon freshwater lake

Contact Info

Product

Resources

About