• Our new home

    since summer 2021.

  • 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

Colocalization and potential interactions of and chlamydiae in microbial aggregates of the coral Pocillopora acuta

Corals are associated with a variety of bacteria, which occur in the surface mucus layer, gastrovascular cavity, skeleton, and tissues. Some tissue-associated bacteria form clusters, termed cell-associated microbial aggregates (CAMAs), which are poorly studied. Here, we provide a comprehensive characterization of CAMAs in the coral . Combining imaging techniques, laser capture microdissection, and amplicon and metagenome sequencing, we show that (i) CAMAs are located in the tentacle tips and may be intracellular; (ii) CAMAs contain (Gammaproteobacteria) and (Chlamydiota) bacteria; (iii) may provide vitamins to its host and use secretion systems and/or pili for colonization and aggregation; (iv) and occur in distinct, but adjacent, CAMAs; and (v) may receive acetate and heme from neighboring . Our study provides detailed insight into coral endosymbionts, thereby improving our understanding of coral physiology and health and providing important knowledge for coral reef conservation in the climate change era.

Maire J, Tandon K, Collingro A, van de Meene A, Damjanovic K, Gotze CR, Stephenson S, Philip GK, Horn M, Cantin NE, Blackall LL, van Oppen MJH
2023 - Sci Adv, 20: eadg0773

Hydrochemical and seasonally conditioned changes of microbial communities in the tufa-forming freshwater network ecosystem

Freshwater network ecosystems consist of interconnected lotic and lentic environments within the same catchment area. Using Plitvice Lakes as an example, we studied the changes in environmental conditions and microbial communities (bacteria and fungi) that occur with downstream flow. Water samples from tributaries, interlake streams, connections of the cascading lakes, and the Korana River, the main outflow of the system, were characterized using amplicon sequencing of bacterial 16S rRNA and fungal ITS2 genes. Our results show that different environmental conditions and bacterial and fungal communities prevail among the three stream types within the freshwater network ecosystem during multiple sampling seasons. Microbial community differences were also confirmed along the longitudinal gradient between the most distant sampling sites. The higher impact of “mass effect” was evident during spring and winter, while “species sorting” and “environmental selection” was more pronounced during summer. Prokaryotic community assembly was majorly influenced by deterministic processes, while fungal community assembly was highly dominated by stochastic processes, more precisely by the undominated fraction, which is not dominated by any process. Despite the differences between stream types, the microbial community of Plitvice Lakes is shown to be very stable by the core microbiome that makes up the majority of stream communities. Our results suggest microbial community succession along the river-lake continuum of microbial communities in small freshwater network ecosystems with developed tufa barriers.
IMPORTANCE Plitvice Lakes represent a rare freshwater ecosystem consisting of a complex network of lakes and waterfalls connecting them, as well as rivers and streams supplying water to the lake basin. The unique geomorphological, hydrological, biogeochemical, and biological phenomenon of Plitvice Lakes lies in the biodynamic process of forming tufa barriers. In addition to microbial communities, abiotic water factors also have a major influence on the formation of tufa. Therefore, it is important to understand how changes in environmental conditions and microbial community assembly affect the functioning of the ecosystem of a freshwater network with developed tufa barriers.

Čačković A, Kajan K, Selak L, Marković T, Brozičević A, Pjevac P, Orlić S
2023 - mSphere, in press

Hot spring distribution and survival mechanisms of thermophilic comammox Nitrospira

The recent discovery of Nitrospira species capable of complete ammonia oxidation (comammox) in non-marine natural and engineered ecosystems under mesothermal conditions has changed our understanding of microbial nitrification. However, little is known about the occurrence of comammox bacteria or their ability to survive in moderately thermal and/or hyperthermal habitats. Here, we report the wide distribution of comammox Nitrospira in five terrestrial hot springs at temperatures ranging from 36 to 80°C and provide metagenome-assembled genomes of 11 new comammox strains. Interestingly, the identification of dissimilatory nitrate reduction to ammonium (DNRA) in thermophilic comammox Nitrospira lineages suggests that they have versatile ecological functions as both sinks and sources of ammonia, in contrast to the described mesophilic comammox lineages, which lack the DNRA pathway. Furthermore, the in situ expression of key genes associated with nitrogen metabolism, thermal adaptation, and oxidative stress confirmed their ability to survive in the studied hot springs and their contribution to nitrification in these environments. Additionally, the smaller genome size and higher GC content, less polar and more charged amino acids in usage profiles, and the expression of a large number of heat shock proteins compared to mesophilic comammox strains presumably confer tolerance to thermal stress. These novel insights into the occurrence, metabolic activity, and adaptation of comammox Nitrospira in thermal habitats further expand our understanding of the global distribution of comammox Nitrospira and have significant implications for how these unique microorganisms have evolved thermal tolerance strategies.

Zhang Y, Liu T, Li MM, Hua Z-S, Evans P, Qu Y, Tan S, Zheng M, Lu H, Jiao J-Y, Lücker S, Daims H, Li W-J, Guo J
2023 - ISME J., in press

Lecture series

DOME Lecture: "Gut microbiome profiling predicts antibiotic resistance of urinary tract infections"

Marta Lukačišinová
EMBO Postdoctoral Research Fellow, Kishony Lab, Technion - Israel Institute of Technology
01.06.2023
12:00 h
hybrid, UBB HS 2

DOME Lecture: "Selection on the accessory genome can predict bacterial evolution"

Bill Hanage
Associate Professor, Harvard TH Chan School of Public Health, USA
21.04.2023
12:00 h
hybrid, UBB HS 2

DOME Lecture: "Recycling versus loss: the pivotal role of nitrite in the marine nitrogen cycle"

Laura Bristow
Assistant Professor for Marine Sciences, University of Gothenburg, Sweden
17.11.2022
12:00 h
hybrid, UBB HS 1