Speth, Daan R.


Publications
8

Identification of key steps in the evolution of anaerobic methanotrophy in Candidatus Methanovorans (ANME-3) archaea

Citation
Woods et al. (2025). Science Advances 11 (25)
Names
Ca. Methanovorans
Abstract
Despite their large environmental impact and multiple independent emergences, the processes leading to the evolution of anaerobic methanotrophic archaea (ANME) remain unclear. This work uses comparative metagenomics of a recently evolved but understudied ANME group, “ Candidatus Methanovorans” (ANME-3), to identify evolutionary processes and innovations at work in ANME, which may be obscured in earlier evolved lineages. We identified horizontal transfer of

Genetic potential for aerobic respiration and denitrification in globally distributed respiratory endosymbionts

Citation
Speth et al. (2024). Nature Communications 15 (1)
Names
Azoamicus ciliaticola Ts Azosocius agrarius Ts Azoamicus soli Azosocius aquiferis Azoamicus viridis Azoamicaceae Azosocius Azoamicales
Abstract
AbstractThe endosymbiont Candidatus Azoamicus ciliaticola was proposed to generate ATP for its eukaryotic host, an anaerobic ciliate of the Plagiopylea class, fulfilling a function analogous to mitochondria in other eukaryotic cells. The discovery of this respiratory endosymbiosis has major implications for both evolutionary history and ecology of microbial eukaryotes. However, with only a single species described, knowledge of its environmental distribution and diversity is limited. Here we rep

Rhizobia–diatom symbiosis fixes missing nitrogen in the ocean

Citation
Tschitschko et al. (2024). Nature 630 (8018)
Names
“Tectiglobus diatomicola”
Abstract
AbstractNitrogen (N2) fixation in oligotrophic surface waters is the main source of new nitrogen to the ocean1 and has a key role in fuelling the biological carbon pump2. Oceanic N2 fixation has been attributed almost exclusively to cyanobacteria, even though genes encoding nitrogenase, the enzyme that fixes N2 into ammonia, are widespread among marine bacteria and archaea3–5. Little is known about these non-cyanobacterial N2 fixers, and direct proof that they can fix nitrogen in the ocean has s

Comparative genomics reveals electron transfer and syntrophic mechanisms differentiating methanotrophic and methanogenic archaea

Citation
Chadwick et al. (2022). PLOS Biology 20 (1)
Names
Ca. Methanovorans
Abstract
The anaerobic oxidation of methane coupled to sulfate reduction is a microbially mediated process requiring a syntrophic partnership between anaerobic methanotrophic (ANME) archaea and sulfate-reducing bacteria (SRB). Based on genome taxonomy, ANME lineages are polyphyletic within the phylumHalobacterota, none of which have been isolated in pure culture. Here, we reconstruct 28 ANME genomes from environmental metagenomes and flow sorted syntrophic consortia. Together with a reanalysis of previou

Draft Genome Sequence of Anammox Bacterium “Candidatus Scalindua brodae,” Obtained Using Differential Coverage Binning of Sequencing Data from Two Reactor Enrichments

Citation
Speth et al. (2015). Genome Announcements 3 (1)
Names
Ca. Scalindua brodae
Abstract
ABSTRACT We present the draft genome of anammox bacterium “ Candidatus Scalindua brodae,” which at 282 contigs is a major improvement over the highly fragmented genome assembly of related species “ Ca. Scalindua profunda” (1,580 contigs) which was previously published.