Defined microbial mixed cultures have a potential to replace biotechnological processes, which are currently accomplished by using a cocktail of purified enzymes. The major advantage of a mixed culture process is a significantly increased efficiency because no separation and purification of the enzyme cocktail is necessary. In addition there is a positive effect on the volumetric productivity because no transfer of enzymes is needed.The utilization of mixed cultures presupposes the optimization of the microbial consortia but so far it can hardly be realized. Offline samples can be taken to quantify the composition but process development and screening for optimal conditions should preferentially be done on the basis of online measured signals. One key question of mixed culture processes is how to distinguish online between single species and to quantify the composition inside the consortium.
MoniCon aims to overcome this limit by the usage of red and green fluorescent proteins. These proteins will be produced by the microorganism and stored inside the cytoplasm (e.g. species A in green, species B in red) and consequently allow for an online detection of the single species. The final aim was the online monitoring of a mixed culture composition consisting of Neurospora crassa and Ustilago maydis, which should be able to produce itaconic acid directly from cellulose. So far it was possible to characterize the U. maydis strains producing red or green fluorescent proteins. With the help of flow cytometry two promoter systems were analyzed and the efficient system was identified. With the help of the BioLector system co-cultures of different U. maydis strains were conducted their respective fluorescence protein made it possible to display different mixing ratios. Also these promising results indicated that it is possible to distinguish between two members of a co-culture, the red fluorescent signal barley described the growth of the single species. Furthermore it was found that the cultivation of N. crassa in liquid medium, an essential requirement for the establishing of the aimed mixed culture, is still challenging.
Participating Core Groups
Prof. Dr.-Ing. Jochen Büchs / Dr. Lars Regestein, AVT - Lehrstuhl für Bioverfahrenstechnik, RTWH Aachen UniversityWorringerweg 3
Phone: +49 241 80 - 28111
Fax: +49 241 80 - 22265
Prof. Dr. Michael Feldbrügge, Dr. Kerstin Schipper, Institut für Mikrobiologie, Heinrich-Heine-Universität Düsseldorf
01.04.2015 - 31.03.2016
MoniCon is part of the NRW-Strategieprojekt BioSC and thus funded by the Ministry of Innovation, Science and Research of the German State of North Rhine-Westphalia.