Microbiology

Michael Wagner is one of the world`s leading researchers in microbial ecology and microbiome analysis. These areas of microbiology deal with the study of the composition and function of microbial communities in the environment and medicine, without which no life on earth would be possible and which are of crucial importance for the health of plants, animals and humans. The diversity of microorganisms on earth is breathtaking and far exceeds that of all other living organisms. However, to date, most microbes cannot be cultivated in the laboratory and studied using conventional microbiology methods. Over the past 25 years, Michael Wagner and his team have developed methods that allow this "dark matter" of microbes to be studied directly in medical or environmental samples for the first time. Not only are the microbes identified directly in the sample to be examined using fluorescence-labeled gene probes without prior cultivation, but their functions are also analyzed at the same time using state-of-the-art chemical imaging methods (NanoSIMS, Raman microspectroscopy). Wagner made a significant contribution to the development of this new field of microbiology and the methods he developed are now used worldwide to analyze microbiomes (the entirety of microbes that colonize a specific ecosystem or humans). Michael Wagner`s current research focuses on microbes that perform essential functions in the global nitrogen cycle. Half of humanity can only be fed through the use of industrially produced nitrogen fertilizer. However, due to the activity of certain groups of microorganisms - the so-called nitrifiers - in agricultural soils, a large proportion of the fertilizer is not absorbed by the plants but ends up in the groundwater, rivers and oceans, where it leads to over-fertilization with dramatic consequences such as algal blooms and the formation of ever-growing "dead zones" in the world`s oceans. As a by-product of their metabolism, nitrifiers also produce significant quantities of nitrous oxide, which is a powerful greenhouse gas and the most important ozone-depleting substance of this century. On the other hand, these nitrifiers contribute significantly to the purification of wastewater in modern sewage treatment plants. Wagner and his team have used their molecular biology and materials science methods to identify a number of novel nitrifiers and have described completely unexpected functional properties of this group of organisms. In 2015, Wagner and his team succeeded in describing and isolating the so-called comammox bacteria for the first time - completely new types of nitrifiers that have fundamentally different metabolic properties and, for example, produce significantly less nitrous oxide than many other nitrifiers. Wagner is currently investigating how microbial communities in soils or sewage treatment plants can be manipulated in such a way that the growth of comammox bacteria can be promoted. The funding from the FWF Wittgenstein Award will allow Wagner to expand the Center for Microbiology and Environmental Systems Research, which was founded at the University of Vienna in 2019, as a world-leading research location in this field. Wagner plans to use the funds from the FWF Wittgenstein Award to develop a new generation of methods for the functional analysis of microbiomes using non-linear Raman spectroscopy (CARS, SRS). If this succeeds, the analysis of the function of individual cells in microbiomes would no longer take hours or days, but could be carried out almost in real time and would thus revolutionize microbiome research. Wagner also plans to incorporate these newly developed methods into a microfluidics-based cell sorter and use them to sort living microbes with defined functions from complex samples for cultivation or genomic analysis at high throughput and, for example, to use these methods to detect completely new types of archaea (a special developmental line of microbes) involved in nitrification in the environment. If these microbes, which have so far only been postulated theoretically, actually exist, this would once again transform our understanding of the global nitrogen cycle and reveal further, previously hidden key players in this important material cycle.