• 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

  • Ancient invaders -

    Bacterial symbionts of amoebae

    and the evolution of the intracellular lifestyle

  • The human microbiome -

    Our own social network of microbial friends

  • 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

  • Apply for the DOME International PhD/PostDoc program

Dome News

  • DoME Participates in the KinderUni 2017

    25.07.17
    News

    In addition to Holger Daims giving one of the opening family lectures, members of the DoMe held multple sessions at this year's KinderUni. These sessions included the following: "A ...

  • ICoN5

    ICoN5 Conference in Vienna

    23.07.17
    Event

    Holger Daims, Michael Wagner and their teams are organizing together with Christa Schleper's group the Fifth International Conference on Nitrification and Related Processes (ICoN5), which is taking place at the campus ...

  • Family lecture at KinderuniWien 2017

    09.07.17
    News

    Holger Daims gave one of the opening family lectures of this year's KinderuniWien. About 300 children (age 7 to 12 years) and parents learned about the human gut microbiome, its ...

  • New FWF project for Holger Daims

    07.07.17
    People

    Holger received funding for a new project from the Austrian Science Fund. Holger will investigate the "Physiology and Environmental Importance of Comammox". 

Latest publications

AmoA-targeted polymerase chain reaction primers for the specific detection and quantification of comammox Nitrospira in the environment

Nitrification, the oxidation of ammonia via nitrite to nitrate, has always been considered to be catalyzed by the concerted activity of ammonia- and nitrite-oxidizing microorganisms. Only recently, complete ammonia oxidizers (‘comammox’), which oxidize ammonia to nitrate on their own, were identified in the bacterial genus Nitrospira, previously assumed to contain only canonical nitrite oxidizers. Nitrospira are widespread in nature, but for assessments of the distribution and functional importance of comammox Nitrospira in ecosystems, cultivation-independent tools to distinguish comammox from strictly nitrite oxidizing Nitrospira are required. Here we developed new PCR primer sets that specifically target the amoA genes coding for subunit A of the distinct ammonia monooxygenase of comammox Nitrospira. While existing primers capture only a fraction of the known comammox amoA diversity, the new primer sets cover as much as 95% of the comammox amoA clade A and 92% of the clade B sequences in a reference database containing 326 comammox amoA genes with sequence information at the primer binding sites. Application of the primers to 13 samples from engineered systems (a groundwater well, drinking water treatment and wastewater treatment plants) and other habitats (rice paddy and forest soils, rice rhizosphere, brackish lake sediment and freshwater biofilm) detected comammox Nitrospira in all samples and revealed a considerable diversity of comammox in most habitats. Excellent primer specificity for comammox amoA was achieved by avoiding the use of highly degenerate primer preparations and by using equimolar mixtures of oligonucleotides that match existing comammox amoA genes. Quantitative PCR with these equimolar primer mixtures was highly sensitive and specific, and enabled the efficient quantification of clade A and clade B comammox amoA gene copy numbers in environmental samples. The measured relative abundances of comammox Nitrospira, compared to canonical ammonia oxidizers, were highly variable across environments. The new comammox amoA-targeted primers enable more encompassing future studies of nitrifying microorganisms in diverse habitats. For example, they may be used to monitor the population dynamics of uncultured comammox organisms under changing environmental conditions and in response to altered treatments in engineered and agricultural ecosystems.

Pjevac P, Schauberger C, Poghosyan L, Herbold CW, van Kessel MAHJ, Daebeler A, Steinberger M, Jetten MSM, Luecker S, Wagner M, Daims H
2017 - Front Microbiol, in press

Genus Terriglobus

Terriglobus is a genus in the phylum Acidobacteria in the family Acidobacteriaceae, order Acidobacteriales, class Acidobacteriia, subdivision 1. It currently comprises five species - Terriglobus roseus, Terriglobus saanensis, Terriglobus tenax, Terriglobus aquaticus, and Terriglobus albidus. Members of the genus are widely distributed in soils including rhizosphere soils and the phyllosphere, but is also found in freshwater and in association with insects. This genus encompasses bacteria that are chemo-organotrophs and have obligatory aerobic metabolism with an optimal growth in mildly acidic (pH ~5 to 6) and mesophilic (ca. 25 to 30°C) conditions. Colonies of Terriglobus are typically circular in form with a convex elevation and can be with or without pink pigmentation. These bacteria can use a range of different carbon sources, and nitrogen is attained by exogenous amino acids or ammonium chloride. Cells are non-motile, Gram-stain-negative with a length and width ranging from 0.8 to 2.5 µm and 0.4 to 0.9 µm, respectively. Some strains produce extracellular material, which can be visualized by microscopy or in liquid culture, generating a floc/clumping phenotype. The dominant fatty acids are iso-C15:0 and C16:1 ω7c/ C16:1 ω6c. The DNA G+C content (mol%) ranges from 57.3 to 63.2%.

2017 - in press. in Bergey’s Manual of Systematics of Archaea and Bacteria. (William B. Whitman). John Wiley & Sons, Chichester, England

Unexpected genomic features in widespread intracellular bacteria: evidence for motility of marine chlamydiae.

Chlamydiae are obligate intracellular bacteria comprising important human pathogens and symbionts of protists. Molecular evidence indicates a tremendous diversity of chlamydiae particularly in marine environments, yet our current knowledge is based mainly on terrestrial representatives. Here we provide first insights into the biology of marine chlamydiae representing three divergent clades. Our analysis of single-cell amplified genomes revealed hallmarks of the chlamydial lifestyle, supporting the ancient origin of their characteristic developmental cycle and major virulence mechanisms. Surprisingly, these chlamydial genomes encode a complete flagellar apparatus, a previously unreported feature. We show that flagella are an ancient trait that was subject to differential gene loss among extant chlamydiae. Together with a chemotaxis system, these marine chlamydiae are likely motile, with flagella potentially playing a role during host cell infection. This study broadens our view on chlamydial biology and indicates a largely underestimated potential to adapt to different hosts and environments.

Collingro A, Köstlbacher S, Mussmann M, Stepanauskas R, Hallam SJ, Horn M
2017 - ISME J, in press

Lecture series

The rapidly expanding universe of giant viruses

Chantal Abergel
Centre National de la Recherche Scientifique & Aix-Marseille University
29.06.2017
16:30 h
Hörsaal 2, UZA 1, Althanstr. 14, 1090 Wien

The importance of growing slowly: roles for redox-active "antibiotics" in microbial survival and development

Dianne Newman
California Institute of Technology
24.05.2017
14:00 h
Hörsaal 2, UZA1, Althanstr. 14, 1090 Wien

Harnessing Bacteria for Drug Discovery: from Bioprospecting to Synthetic Biology

Sergey Zotchev
Department of Pharmacognosy, University of Vienna
26.01.2017
12:00 h
Hörsaal 2. (UZA I), Althanstrasse 14, A-1090 Vienna