PSC Frontier Seminar series
Title: Exploring the genomes of extremophilic red algae Galdieria to unlock diversities in metabolic survival
Speaker: Prof. Seth J. Davis, University of York
Time: 10:00 am
Day/Date: December 14th, 2018 (Friday)
Host PI: Prof. Yuehui He
Venue: PSC Auditorium
Galdieria species are extremophilic eukaryotic microalgae with amazing diversity of metabolism, essentially unparalleled in the eukaryotic kingdom. Galdieria thrives to pH = 0 and 56˚C, the limits of eukaryotic life, can grow as an aerobic autotroph in the light and as a heterotroph in the dark; it also grows anaerobically in 100% N2 in the dark if supplied a carbon source and in 100% CO2 in the light. Members in this genus display broad metabolic repertoires allowing vigorous growth on nearly any carbon source, including all sugar, sugar-alcohol or organic-acid sources. They are known to detoxify contaminants under high concentrations of toxic metals and thus are targets for bespoke bio-mining applications for precious metal and rare-earth metal accumulation. Full genome sequencing serves as a start to explore this diversity. Estimates of the chromosome number of Galdieria sulphuraria previously ranged from 2 to 57. We report here that we have sequenced the nuclear and organellar genome of G. sulphuraria to completion using Oxford Nanopore long-read sequencing. The produced assemblies are entire chromosomes including intact subtelomeres and telomeres. Using this first ever telomere-to-telomere sequencing via long-range genomics, we found that G. sulphuraria has 72 nuclear chromosomes. This can explain how G. sulphuraria responds rapidly to adaptive shifts in extreme environments, as large numbers of small chromosomes could easily generate highly novel chromosome combinations to support a eukaryotic extremophilic life.
The seminar will be delivered in English.