Dr. Antonis Chatzinotas

CV / Scientific Career

Research interests

I am interested in understanding the diversity, functioning and ecosystem processes of microbial communities (bacteria, protists, phage) in natural and engineered ecosystems (e.g. lakes, rivers, aquifers, soils, wastewater treatment plants).

My research addresses amongst others

(i) the response of microbial communities and functions to environmental change and human activities,

(ii) the interactions within and between different trophic levels (bacteria, eukaryotic (micro)organisms, phages),

(iii) the evaluation of ecological theories in microbial ecology.

The aim of these studies is not only to increase our knowledge regarding the phylogenetic and functional diversity of microorganisms, but also to better understand the role of interactions between different trophic levels (bacteria, protists, phages, fungi and plants) for ecosystem functioning under changing environmental conditions.

Microbial diversity and functioning. We are studying how environmental parameters and human activities affect microbial communities, their functions and distribution in ecosystems. These impacts include e.g. industrial pollution, land use gradients or extrem weather events. Analysis of microbial communities is mainly based on cultivation-independent methods including high throughput sequencing and omics-approaches, but requires in some cases also alternative cultivation approaches. Functional bacterial groups involved e.g. in the degradation of pollutants are identified by applying 13C-labelled substrates and stable isotope probing (SIP). A recent, new focus is the role of the flexible gene pool (e.g. plasmids) for the adaptation of aquatic bacteria to changing environmental condition (antibiotic resistance genes or genes involved in BTEX degradation).

Interactions within and between different trophic levels. Understanding the interactions within the same and between different trophic levels is required for a full comprehension of of microbial communities and processes, particularly in response to changes in their abiotic and biotic environment. We are for instance studying the role of micropredators (i.e. predatory bacteria, protists, phages) for an efficient removal of bacterial pathogens in WWTP. Trophic interactions in the degradation of macromolecules (cellulose, chitin) are addressed using SIP. With respect to plant-microbe interactions, we are currently investigating the cascading effect of rhizophere microbial interactions on plant metabolite profiles. Phage ecology and (meta)genomics as well as specific phage-bacteria interactions are adresses in constructed wetlands, in subsurface and freshwater systems.

Ecological theories. Next to working on field sites, we apply (often very simple) microbial model systems to address key principles in ecological theories. Since microorganisms are the key players in many ecosystems, it is necessary to bridge the gap between microbial ecology and general ecology. Such model systems enable a high degree of replication and experimental control and are helpful to test the applicability of ecological concepts and theories derived from experiments with higher organisms. We further test the applicablilty of ecological concepts to improve biotechnological applications with microbes.

Ongoing research cooperations

Virus/Phage ecology in soil (with TU Munich, Helmholtz Zentrum Munich)

Phage diversity and phage-host interactions in subsurface systems (DFG-SFB AquaDiva) and rivers (with Department River Ecology, UFZ)

Microbiomes and microbial interactions in rivers (with Department River Ecology, UFZ)

Dog Microbiome studies (with Veterinary Medicine Leipzig)

Micropredators controlling bacterial pathogens in aquatic systems: Ecological and evolutionary consequences (with Hebrew University of Jerusalem, Ben Gurion University, University Bethlehem (DFG-Trilateral MICROPRED))

Protist-BALO interactions (with University Kiel)

Publications