How cyclic peptides from cyanobacteria influence biodiversity?

The main goal of the proposed project is to investigate how various cyclic peptides that are simultaneously released from cyanobacterial cells, affect different organisms that come in contact with them and how they affect biodiversity. Namely there are several indications that cyclic peptides from cyanobacteria lower the biodiversity. Firstly we will isolate and optimize the isolation of different cyclic peptides from cyanobacterial cells. Isolated and purified cyclic peptides will be tested in vitro on different phytoplankton representatives. We will monitor the effects on the cellular as well as on the subcellular level by HPLC, epifluorescent and confocal laser microscope. In natural environment the organisms are never exposed only to an isolated biologically active substance, therefore we will study the possible co-operative effects of different cyclic peptides that are usually produced in bloom forming cyanobacteria such as microcystins and cyclic depsipeptides. This is our next step in order to determine the ecological role of cyclic peptides in the water environment and in the origin of cyanobacterial blooms. The importance of this work is a contribution to preservation of biodiversity in water environment.