The development of new micrometer-scale sensors for analysis of microbial metabolism has been a core activity for many years, and it will also be an important activity during Revsbech’s 12 months at AIAS. By use of such sensors it has been possible to analyse the chemical microenvironment of microorganisms growing in substrates such as sediments at high resolution, and it is even possible to calculate local transformation rates of photosynthesis and various types of respiration from the data.
Niels Peter Revsbech will focus on the development of novel microscale sensors for nitrous oxide and carbon dioxide, as knowledge about the transformations of both these chemical species is important in contexts of both applied and basic research. Simultaneous with the development of novel sensors, Revsbech will try to improve already functioning sensors developed earlier, and here focus will be on a hydrogen microsensor developed in 2012 and on ultra-sensitive oxygen sensors that we have been using extensively during the last 5 years. The already existing sensor technology developed in my laboratory will be applied in several contexts. Together with his collaborators Revsbech will thus analyse hydrogen transformation in biogas reactors in Denmark and hot springs of Yellowstone National Park, the kinetics of oxygen consumption in seawater (Denmark, Costa Rica, Mexico) and in pure cultures of bacteria, and effects of nanomolar concentrations of oxygen on nitrogen transformations (Costa Rica).
The proposed work will not only result in novel insights into processes in nature, but will also be crucial for the general development of reliable procedures for measuring transformation rates in nature, as high-resolution data obtained with microsensors often illustrate the limitations of other methods.
Niels Peter Revsbech is a Jens Christian Skou Senior Fellow at the Aarhus Institute of Advanced Studies. He received his PhD from Aarhus University in 1981. He has held postdoc positions in Montana and Michigan in 1981-1982 as well as positions as postdoc, assistant professor and associate professor at Aarhus University from 1982-1997. He is a professor in Microbial Ecology at Aarhus University, a position that he still holds. Revsbech has developed various needle-shaped electrochemical sensors for analysis of microbial communities. The environments analysed include marine and freshwater sediments, soils, hot springs, hypersaline lakes, wastewater treatment plants and oceanic oxygen minimum zones.