Journal of Biotechnology & Biomaterials
Open Access

Abstract

The interaction of microorganisms with chemical effectors, combinatorial effects on single organisms and microbial communication are crucial topics for ecology, medicine, drug development and food production. In particular, natural microorganism communities are highly dynamic system, which are modulated in their composition and activity by physical and chemical factors. It has to be assumed that soils and other natural systems contain a restricted number of active species, but a high number of species in a dormant state which are activated only in case of changing environmental conditions. The apparent discrepancy between the very high diversity concluded from metagenomic data and the number of isolated microorganisms can be interpreted by the existence of this huge majority of species which carries the principle ecological potential of a soil to respond to a large spectrum of different conditions. There is a strong demand for the development of new strategies for the evaluation of the ecological function and the synthesis potential of known and unknown microorganisms. The complexity of the problem is enhanced by organism interactions beside temperature, and the content of minerals, nutrients and humidity. The technique of micro-segmented flow can mimic to a certain extent the natural situation of complex habitats in laboratory screenings. It allows to subdivide samples containing mixtures of microorganisms into small fractions and to cultivate them under well-defined conditions in large sample sets. In particular, this technique is suited for the variation of concentrations of effector substances and for the determination of highly resolved dose/response functions. This potential was used for the evaluation of response of different bacteria and eukaryotic microorganisms on antibiotics, heavy metal ions, nanoparticles, pharmaceutical drugs and other substances as well as for studying combinatorial effects of these substances. In many cases, sharp transitions between undisturbed growth and growth suppression have been observed, which speak for â�?�?switch-likeâ�? effects of critical effector concentrations. In binary studies, all types of combinatorial effects as additives, independent effects, synergy, antagonism and complex responses have been observed. The technique can also be applied for the evaluation of artificial and natural communities.

Biography

Email: Johann.Kohler@etit.tu-chemnitz.de