P13 - Kinetics & Microzymography

Microbial life in the rhizosphere: kinetics and visualization of the functions


The soil biogeochemical processes are mainly microbially mediated; therefore, their localization is restricted to microbial habitats occurring at micro-scale (microbial hotspots). Rhizosphere hotspots are the most important plant-soil interfaces with very dynamic interactions between roots and microorganisms, resulting in non-uniform distribution of microbial activity in micro-space.
The project Microzym focuses on self-regulatory mechanisms of the rhizosphere organization through visualized localization of sequence of processes from the input of root exudates to the soil until their decomposition/mineralization. The novelty of Microzym is in estimation of in situ process rates in soil depending on physiological state of soil microbial communities and considering microbial competition driven by inverse gradients of labile C and nutrients within and between rhizosphere hotspots. This will be done by the combination of new approaches coupling visualization of rhizosphere processes with estimation of kinetic parameters of microbial and enzymatic activity, nutrients uptake and substrate turnover. This project considers 1) the improvement and mitigation the shortcomings of the 2D zymography, 2) developing the micro-zymography, 3) development the non-destructive measurements of enzyme kinetics in soil solution and 4) determining the kinetic parameters of microbial growth in the rhizosphere hotspots. Finally, the Microzym will link a localization of the rhizosphere processes (e.g., decomposition of organic substrates) with their rates and with functional traits of dominating microbial populations.

Link to English scientific abstract

Link to German scientific abstract