Abstract Title
Diverse genome sequences from recent toxic and non-toxic US Pacific Northwest freshwater HABs belong to the Nostocales ADA clade
Start Date
25-5-2022 9:15 AM
End Date
25-5-2022 9:30 AM
Abstract
Combined PacBio long-read and Illumina short-read DNA sequencing has recently allowed us to determine the genome sequences (without cultivation) of the main cyanobacteria present in recent freshwater HABs from the US Pacific NW. Our studies have emphasized blooms in multiple lakes that were dominated by Nostocales cyanobacteria. The 12 Dolichospermum and 5 Aphanizomenon flos-aquae genomes that we have assembled all represent members of the Nostocales ADA clade. Non-toxigenic members are included, as well as verified producers of microcystin (MC-LR, [Dha7]MC-HtyR), 7-epi-cylindrospermopsin and anatoxin-a. The ADA genomes are a genetically diverse group that we propose belong to 4 of 10 species that comprise an ADA genus, which includes Dolichospermum, Aphanizomenon flos-aquae, benthic Anabaena and Cuspidothrix. We have also assembled 3 Gloeotrichia echinulata genomes, all of which possess geosmin synthase but lack cyanotoxin genes. The relationships between geography, morphology and genotype will be described, as well as different patterns of genome evolution between ADA members and Gloeotrichia.
Diverse genome sequences from recent toxic and non-toxic US Pacific Northwest freshwater HABs belong to the Nostocales ADA clade
Combined PacBio long-read and Illumina short-read DNA sequencing has recently allowed us to determine the genome sequences (without cultivation) of the main cyanobacteria present in recent freshwater HABs from the US Pacific NW. Our studies have emphasized blooms in multiple lakes that were dominated by Nostocales cyanobacteria. The 12 Dolichospermum and 5 Aphanizomenon flos-aquae genomes that we have assembled all represent members of the Nostocales ADA clade. Non-toxigenic members are included, as well as verified producers of microcystin (MC-LR, [Dha7]MC-HtyR), 7-epi-cylindrospermopsin and anatoxin-a. The ADA genomes are a genetically diverse group that we propose belong to 4 of 10 species that comprise an ADA genus, which includes Dolichospermum, Aphanizomenon flos-aquae, benthic Anabaena and Cuspidothrix. We have also assembled 3 Gloeotrichia echinulata genomes, all of which possess geosmin synthase but lack cyanotoxin genes. The relationships between geography, morphology and genotype will be described, as well as different patterns of genome evolution between ADA members and Gloeotrichia.