Towards the investigation of microbe-mineral interaction by means of Raman spectroscopy
The aim of this doctoral thesis is to gain more information about the interaction processes which take place in nature between the biotic and abiotic components. The ultimate goal is to be able to increase the bioremediation rate by modifying accordingly the factors which influence the bioremediation. To be able to reach this goal, detailed studies focused on biomineralization, biotransformation and biodissolution are required. The influences of various geochemical factors on the microbial communities of an environment, and the response of microorganisms to those factors have to be studied. Furthermore, information regarding the identity of the microorganisms forming the microbial consortium and their role played in the investigated environment is imperatively necessary. Previous investigations have shown that bulk and single cell bacterial identification is doable by means of Raman spectroscopy. In addition, Raman spectroscopy can be used for identification of minerals, organic matter, liquids or gases presented in the rocks. The high sensitivity, the minimal sample preparation and the possibility to investigate minerals instable at atmospheric conditions makes Raman spectroscopy a valuable tool for the investigation of the minerals. The interaction between the biotic and the abiotic components of an iron contaminated aquatic environment was the main topic of this doctoral thesis . The investigation of the bacterial-mineral interactions implies two studies: the influence of the microbial communities on the mineral phases of the pelagic aggregates, and the effect of the geochemical conditions of the aquatic environment on the microbial consortia. In addition to these studies, investigation of biologically mediated iron-rich sedimentary rocks was also performed, emphasizing the potential application of Raman spectroscopy in the field of microbe-mineral interaction.