• CUBE - Computational Systems Biology

  • DOME - Microbial Ecology

  • TER - Terrestrial Ecosystem Research

  • We establish and analyse

    quantitative mathematical models.

  • We develop, improve and apply

    computational methods

    for the interpretation of molecular information in biology.

  • Our aim is to advance our understanding of biological systems,

    ranging from single species to multi-species systems and ecosystems,

    based on data from large-scale bioanalytical methods.

DMES News

  • Happy new year 2019

    01.01.19
    Event

    CUBE wishes all colleagues and friends a happy and successful new year 2019!

  • New paper in Nature Biotechnology

    21.12.18
    Publication

    A new paper in Nature BIotechnology introduces quality and data standards for viral metagenomics and genomes of uncultivable viruses.

  • New FWF project for Alexander Loy

    07.12.18
    News

    Alex received funding for his project "The wetland sulfur microbiome - intra- and interspecies metabolic interactions" from the Austrian Science Fund. Congratulations!

  • Hiring: Open group leader position at CUBE

    05.12.18
    Personal

    We are seeking to fill a Group leader (Senior PostDoc) position in CUBE. The Group leader will actively contribute to teaching in bioinformatics, perform independent research in bioinformatics and contribute to the self-administration of the university.

    Read more... ...

Latest publications

Long-term transcriptional activity at zero growth by a cosmopolitan rare biosphere member

Microbial diversity in the environment is mainly concealed within the rare biosphere (all species with <0.1% relative abundance). While dormancy explains a low-abundance state very well, the mechanisms leading to rare but active microorganisms remain elusive. We used environmental systems biology to genomically and transcriptionally characterise Candidatus Desulfosporosinus infrequens, a low-abundance sulfate-reducing microorganism cosmopolitan to freshwater wetlands, where it contributes to cryptic sulfur cycling. We obtained its near-complete genome by metagenomics of acidic peat soil. In addition, we analyzed anoxic peat soil incubated under in situ-like conditions for 50 days by Desulfosporosinus-targeted qPCR and metatranscriptomics. The Desulfosporosinus population stayed at a constant low abundance under all incubation conditions, averaging 1.2 × 10⁶ 16S rRNA gene copies per cm³ soil. In contrast, transcriptional activity of Ca.D. infrequens increased at day 36 by 56- to 188-fold when minor amendments of acetate, propionate, lactate, or butyrate were provided with sulfate, as compared to the no-substrate-control. Overall transcriptional activity was driven by expression of genes encoding ribosomal proteins, energy metabolism and stress response but not by expression of genes encoding cell growth-associated processes. Since our results did not support growth of these highly active microorganisms in terms of biomass increase or cell division, they had to invest their sole energy for maintenance, most likely counterbalancing acidic pH conditions. This finding explains how a rare biosphere member can contribute to a biogeochemically relevant process while remaining in a zero growth state over a period of 50 days.

Hausmann B, Pelikan C, Rattei T, Loy A, Pester M
2019 - mBio, In press

Novel high-throughput approach to determine key processes of soil organic nitrogen cycling: Gross protein depolymerization and microbial amino acid uptake

Proteins comprise the largest soil N reservoir but cannot be taken up directly by microorganisms and plants due to size constraints and stabilization of proteins in organo-mineral associations. Therefore the cleavage of this high molecular weight organic N to smaller soluble compounds as amino acids is a key step in the terrestrial N cycle. In the last years two isotope pool dilution approaches have been successfully established to measure gross rates of protein depolymerization and microbial amino acid uptake in soils. However, both require laborious sample preparation and analyses, which limits sample throughput. Therefore, we here present a novel isotope pool dilution approach based on the addition of 15N-labeled amino acids to soils and subsequent concentration and 15N analysis by the oxidation of α-amino groups to NO2 and further reduction to N2O, followed by purge-and-trap isotope ratio mass spectrometry (PT-IRMS). We applied this method in mesocosm experiments with forest and meadow soils as well as with a cropland soil amended with either organic C (cellulose) or organic N (bovine serum albumin). To measure direct organic N mineralization to NH4+, the latter was captured in acid traps and analyzed by an elemental analyzer coupled to an isotope ratio mass spectrometer (EA-IRMS). Our results demonstrate that the proposed method provides fast and precise measurements of at%15N even at low amino acid concentrations, allows high sample throughput and enables parallel estimations of instantaneous organic N mineralization rates.

Noll L, zhang S, Wanek W
2019 - Soil Biology and Biochemistry, 130: 73-81

Growth explains microbial carbon use efficiency across soils differing in land use and geology

The ratio of carbon (C) that is invested into microbial growth to organic C taken up is known as microbial carbon use efficiency (CUE), which is influenced by environmental factors such as soil temperature and soil moisture. How microbes will physiologically react to short-term environmental changes is not well understood, primarily due to methodological restrictions. Here we report on two independent laboratory experiments to explore short-term temperature and soil moisture effects on soil microbial physiology(i.e. respiration, growth, CUE, and microbial biomass turnover): (i) a temperature experiment with 1-day pre-incubation at 5, 15 and 25 °C at 60% water holding capacity (WHC), and (ii) a soil moisture/oxygen (O2) experiment with 7-day pre-incubation at 20 °C at 30%, 60% WHC (both at 21% O2) and 90% WHC at 1% O2. Experiments were conducted with soils from arable, pasture and forest sites derived from both silicate and limestone bedrocks. We found that microbial CUE responded heterogeneously though overall positively to short-term temperature changes, and decreased significantly under high moisture level (90% WHC)/suboxic conditions due to strong decreases in microbial growth. Microbial biomass turnover time decreased dramatically with increasing temperature, and increased significantly at high moisture level (90% WHC)/suboxic conditions. Our findings reveal that the responses of microbial CUE and microbial biomass turnover to short-term temperature and moisture/O2 changes depended mainly on microbial growth responses and less on respiration responses to the environmental cues, which were consistent across soils differing in land use and geology.

Zheng Q, Hu Y, zhang S, Noll L, Boeckle T, Richter A, Wanek W
2019 - Soil Biology and Biochemistry, 128: 45-55