Abstract Title

Insights from the global pangenome of Raphidiopsis raciborskii

Presenter Information

Anusuya Willis, CSIROFollow

Start Date

25-5-2022 11:30 AM

End Date

25-5-2022 11:45 AM

Abstract

Anusuya Willis, Jason Woodhouse, and a global network of participants*.

Raphidiopsis raciborskii is a species, including both toxic and non-toxic strains. It occurs, and frequently blooms, in freshwater ecosystems across tropical and temperate environments. Local scale studies have shown high physiological and genomic diversity between strains of R. raciborskii, indicating possible rapid adaptation to new environments and resilience to environmental changes.

To investigate the global genomic diversity of R. raciborskii we sequenced the full genomes of ~85 strains from 22 countries, spanning the continents Africa, America, Asia, Australia, and Europe.

Comparative genomics show a small core genome and a large variable shell genome, suggesting a flexible genome evolution strategy. However, many gene presence/absences appear to be redundant and overall metabolic functions are similar across all genomes. There is a lack of unique features within each cluster and genome structural changes appear haphazard across the genome. These genomes are particularly rich in anti-phage systems, with over 500 CRISPR arrays, suggesting high rates of phage interaction.

Speciation is occurring through geographic isolation, and three distinct species clusters were evidenced, indicating taxonomic changes and new species descriptions are needed within Raphidiopsis.

The Raphidiopsis global pangenome reveals species with a flexible genome and local adaptation without local functional differences.

*global network of participants:

Anusuya Willis and Ian Jameson; Australian National Algae Culture Collection, CSIRO, Hobart, TAS, Australia

Catharina Alves-de-Souza; Algae Resource Centre, University of North Carolina Wilmington, USA

Cecile Bernard and Charlotte Duval; Muséum National d’Histoire Naturelle, Paris, France

Masanobu Kawachi and Haruyo Yamaguchi; National Institute for Environmental Studies (NIES), Tsukuba, Japan

Ruth N. Levy-Kaplan; Israel National Culture Collection of Algae, Kinneret Limnological Laboratory, Israel Oceanographic & Limnological research, Israel

Alescia Cullen and Brett Neilan; University of Newcastle, Australia

Maxine A. D. Mowe, Darren C. J. Yeo; National University of Singapore, Singapore

Simon M. Mitrovic; University of Technology Sydney, Australia

Dariusz Dziga; Laboratory of Metabolomics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland

Mikołaj Kokociński; Department of Hydrobiology , Faculty of Biology, Adam Mickiewicz University, Poznań, Poland

Jun Yang; Aquatic EcoHealth Group, Fujian Key Laboratory of Watershed Ecology, Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China

Gaetan Burgio: John Curtin School of Medical Research, ANU College of Health and Medicine, The Australia National University, Canberra, Australia

Muriel Gugger; Cyanobacteria Culture Collection of Cyanobacteria, Pasteur Culture of Cyanobacteria, Institut Pasteur Institute, Université de Paris, Paris, France

Jason Woodhouse; Dept. of Experimental Limnology, Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), 16775 Stechlin, Germany

This document is currently not available here.

COinS
 
May 25th, 11:30 AM May 25th, 11:45 AM

Insights from the global pangenome of Raphidiopsis raciborskii

Anusuya Willis, Jason Woodhouse, and a global network of participants*.

Raphidiopsis raciborskii is a species, including both toxic and non-toxic strains. It occurs, and frequently blooms, in freshwater ecosystems across tropical and temperate environments. Local scale studies have shown high physiological and genomic diversity between strains of R. raciborskii, indicating possible rapid adaptation to new environments and resilience to environmental changes.

To investigate the global genomic diversity of R. raciborskii we sequenced the full genomes of ~85 strains from 22 countries, spanning the continents Africa, America, Asia, Australia, and Europe.

Comparative genomics show a small core genome and a large variable shell genome, suggesting a flexible genome evolution strategy. However, many gene presence/absences appear to be redundant and overall metabolic functions are similar across all genomes. There is a lack of unique features within each cluster and genome structural changes appear haphazard across the genome. These genomes are particularly rich in anti-phage systems, with over 500 CRISPR arrays, suggesting high rates of phage interaction.

Speciation is occurring through geographic isolation, and three distinct species clusters were evidenced, indicating taxonomic changes and new species descriptions are needed within Raphidiopsis.

The Raphidiopsis global pangenome reveals species with a flexible genome and local adaptation without local functional differences.

*global network of participants:

Anusuya Willis and Ian Jameson; Australian National Algae Culture Collection, CSIRO, Hobart, TAS, Australia

Catharina Alves-de-Souza; Algae Resource Centre, University of North Carolina Wilmington, USA

Cecile Bernard and Charlotte Duval; Muséum National d’Histoire Naturelle, Paris, France

Masanobu Kawachi and Haruyo Yamaguchi; National Institute for Environmental Studies (NIES), Tsukuba, Japan

Ruth N. Levy-Kaplan; Israel National Culture Collection of Algae, Kinneret Limnological Laboratory, Israel Oceanographic & Limnological research, Israel

Alescia Cullen and Brett Neilan; University of Newcastle, Australia

Maxine A. D. Mowe, Darren C. J. Yeo; National University of Singapore, Singapore

Simon M. Mitrovic; University of Technology Sydney, Australia

Dariusz Dziga; Laboratory of Metabolomics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland

Mikołaj Kokociński; Department of Hydrobiology , Faculty of Biology, Adam Mickiewicz University, Poznań, Poland

Jun Yang; Aquatic EcoHealth Group, Fujian Key Laboratory of Watershed Ecology, Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China

Gaetan Burgio: John Curtin School of Medical Research, ANU College of Health and Medicine, The Australia National University, Canberra, Australia

Muriel Gugger; Cyanobacteria Culture Collection of Cyanobacteria, Pasteur Culture of Cyanobacteria, Institut Pasteur Institute, Université de Paris, Paris, France

Jason Woodhouse; Dept. of Experimental Limnology, Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), 16775 Stechlin, Germany