Michel Denis (MIO)
Tina Silovic (OT-Med post-doc)
Cytobuoy bv, NL (SME)
DHEMISA aims to investigate the dynamics of aquatic heterotrophic microorganisms, from heterotrophic prokaryotes to microzooplankton, with a new automated flow cytometer (Cytopro) specially designed for this purpose by both an EU SME (Cytobuoy bv, NL) and academic laboratory (MIO / IRSTEA).
The project focuses on validating the Cytopro automated cytometer and developing its application to study the dynamics of heterotrophic microorganisms in a laboratory and in situ, (1) in the Berre Lagoon and in a (2) Mediterranean lake, ideally by relating food web structure to the ecosystem functioning characteristics (organic matter degradation and ecosystem metabolism).
This new tool addresses simultaneously mineralisers and grazers and contributes to the quantification of organic matter mineralisation and its transfer to higher trophic levels. In situ high frequency observation of heterotrophic microorganisms at the single cell level is a prerequisite to achieve a better characterisation and quantification of the dynamics of both their biological activity and their interaction with the autotrophic compartment.
The ultimate stage of DHEMISA project is the coupling of Cytosense and Cytopro instruments to address simultaneously the short term variations of both compartments (phytoplankton and heterotrophic microorganisms). This target represents a real breakthrough in the field of microbial ecology.
Tis project contributed to 2 prototypes of Cytopro built by Cytobuoy.
- Steps validated on the 1st prototype: the first prototype was not working at all
- Steps validated on the 2nd prototype: the second staining module was more in line with the initial principle scheme sent to Cytobuoy by the MIO team. The efficiency of the staining module could thus be validated as well as its coupling to the automated flow cytometer.
Picture of the second Cytopro prototype with the automated flow cytometer on top of its staining module attachment.