• Hunting for microbes since 2003

  • We seek to understand

    the role of microorganisms in Earth's nutrient cycles

    and as symbionts of other organisms

  • Cycling of carbon, nitrogen and sulfur

    affect the health of our planet

  • The human microbiome -

    Our own social network of microbial friends

  • Ancient invaders -

    Bacterial symbionts of amoebae

    and the evolution of the intracellular lifestyle

  • Marine symbioses:

    Listening in on conversations

    between animals and the microbes they can't live without

  • Single cell techniques offer new insights

    into the ecology of microbes

  • Doctoral School in Microbiology and Environmental Sciences

  • PhD program in Microbial Symbioses

    A special FWF funded track in our doctoral school

Dome News

Latest publications

Metabolic and phylogenetic diversity in the phylum Nitrospinota revealed by comparative genome analyses

The most abundant known nitrite-oxidizing bacteria in the marine water column belong to the phylum Nitrospinota. Despite their importance in marine nitrogen cycling and primary production, there are only few cultured representatives that all belong to the class Nitrospinia. Moreover, although Nitrospinota were traditionally thought to be restricted to marine environments, metagenome-assembled genomes have also been recovered from groundwater. Over the recent years, metagenomic sequencing has led to the discovery of several novel classes of Nitrospinota (UBA9942, UBA7883, 2-12-FULL-45-22, JACRGO01, JADGAW01), which remain uncultivated and have not been analyzed in detail. Here, we analyzed a nonredundant set of 98 Nitrospinota genomes with focus on these understudied Nitrospinota classes and compared their metabolic profiles to get insights into their potential role in biogeochemical element cycling. Based on phylogenomic analysis and average amino acid identities, the highly diverse phylum Nitrospinota could be divided into at least 33 different genera, partly with quite distinct metabolic capacities. Our analysis shows that not all Nitrospinota are nitrite oxidizers and that members of this phylum have the genomic potential to use sulfide and hydrogen for energy conservation. This study expands our knowledge of the phylogeny and potential ecophysiology of the phylum Nitrospinota and offers new avenues for the isolation and cultivation of these elusive bacteria.

Kop LFM, Koch H, Jetten MSM, Daims H, Lücker S
2024 - ISME Commun., 4: ycad017

Viral potential to modulate microbial methane metabolism varies by habitat.

Methane is a potent greenhouse gas contributing to global warming. Microorganisms largely drive the biogeochemical cycling of methane, yet little is known about viral contributions to methane metabolism (MM). We analyzed 982 publicly available metagenomes from host-associated and environmental habitats containing microbial MM genes, expanding the known MM auxiliary metabolic genes (AMGs) from three to 24, including seven genes exclusive to MM pathways. These AMGs are recovered on 911 viral contigs predicted to infect 14 prokaryotic phyla including Halobacteriota, Methanobacteriota, and Thermoproteota. Of those 24, most were encoded by viruses from rumen (16/24), with substantially fewer by viruses from environmental habitats (0-7/24). To search for additional MM AMGs from an environmental habitat, we generate metagenomes from methane-rich sediments in Vrana Lake, Croatia. Therein, we find diverse viral communities, with most viruses predicted to infect methanogens and methanotrophs and some encoding 13 AMGs that can modulate host metabolisms. However, none of these AMGs directly participate in MM pathways. Together these findings suggest that the extent to which viruses use AMGs to modulate host metabolic processes (e.g., MM) varies depending on the ecological properties of the habitat in which they dwell and is not always predictable by habitat biogeochemical properties.

Zhong ZP, Du J, Köstlbacher S, Pjevac P, Orlić S, Sullivan MB
2024 - Nat Commun, 1: 1857

The maternal microbiome in pregnancy, delivery, and early-stage development of neonatal microbiome after cesarean section: A prospective longitudinal study.

Changes within the maternal microbiome during the last trimester of pregnancy and the determinants of the subsequent neonatal microbiome establishment after delivery by elective cesarean section are described.
Maternal vaginal and rectal microbiome samples were collected in the last trimester and before cesarean section; intrauterine cavity, placenta, neonatal buccal mucosa, skin, and meconium samples were obtained at birth; neonatal sample collection was repeated 2-3 days postnatally. Microbial community composition was analyzed by 16S rRNA gene amplicon sequencing. Relative abundance measurements of amplicon sequencing variants and sum counts at higher taxonomic levels were compared to test for significant overlap or differences in microbial community compositions.
gov ID: NCT04489056.
A total of 30 mothers and their neonates were included with available microbiome samples for all maternal, intrauterine cavity and placenta samples, as well as for 18 of 30 neonates. The composition of maternal vaginal and rectal microbiomes during the last trimester of healthy pregnancies did not significantly change (permutational multivariate analysis of variance [PERMANOVA], p > 0.05). No robust microbial signature was detected in the intrauterine cavity, placenta, neonatal buccal mucosa, skin swabs, or meconium samples collected at birth. After birth, the neonatal microbiome was rapidly established, and significantly different microbial communities were detectable 2-3 days postnatally in neonate buccal mucosa and stool samples (PERMANOVA, p < 0.01).
Maternal vaginal and rectal microbiomes in healthy pregnancies remain stable during the third trimester. No microbial colonization of the neonate was observed before birth in healthy pregnancies. Neonatal microbiomes in infants delivered by cesarean section displayed a taxonomic composition distinct from maternal vaginal and rectal microbiomes at birth, indicating that postnatal exposure to the extrauterine environment is the driving source of initial neonatal microbiome development in this cohort.

Foessleitner P, Pjevac P, Granser S, Wisgrill L, Pummer L, Eckel F, Seki D, Berry D, Hausmann B, Farr A
2024 - Acta Obstet Gynecol Scand, in press

Lecture series

CANCELLED!! DOME Lecture: "Iron-sulfur proteins in microbial sulfur oxidation"

Christiane Dahl
Research Group Leader, University of Bonn, Germany
12:00 h

CANCELLED!! DOME Lecture: "Phage communication: from mechanisms to ecology and evolution"

Avigdor Eldar
Associate Professor, Tel-Aviv University, Israel
12:00 h

CANCELLED!! DOME Lecture: "Genomes in Rhodnius prolixus symbiotic system"

Eva Nováková
Associate Professor, University of South Bohemia, Czech Republic
12:00 h