In this master's thesis we tested the recognition between swarming Bacillus subtilis isolates obtained from the tomato rhizosphere on a semi-solid medium (co-mentor the project manager, Dr. Štefanič, mentor dr. Kraigher). Additionally, we checked whether the recognition / discrimination between the isolates is correlated with the competition for the root colonization. The results have shown that discrimination between the isolates prevailed as mostly demarcation lines between the swarms were observed. Additionally, discrimination between the swarms was correlated with the competition for the root colonization, where only kin strains could co-exist on the root, while non-kin strains excluded each other. We have successfully implemented and optimized the method for testing the competition for the colonization of the Arabidopsis thaliana root, which will be very useful in further studies of interactions between bacteria.
D.10 Educational activities
COBISS.SI-ID: 4844920Within the framework of this master's thesis (co-mentor the project manager, Dr. Štefanič, mentor Prof. dr. Mandič-Mulec), the candidate investigated the influence of kin discrimination on the horizontal gene transfer in Bacillus subtilis. To test this, the strains of B. subtilis were isolated from the soil micro-scale environment with known affinities (kin and non-kin). She prepared a set of antibiotic-resistant recombinant (SpR or CmR) and a fluorescence marker (cfp or yfp) strains, which allowed us to experimentally follow the horizontal DNA transfer between the strains. Border lines that formed between two non kin strains were tested by selecting transformants resistant to both antibiotics, carried by the two strains. The results of this master thesis showed that DNA exchange is more frequent at the boundary between swarms of less related 'non-kin' strains, than between more related 'kin' strains. Our findings enable further research of 'kin' recognition among B. subtilis strains and thus better understanding of soil bacteria interactions and their mechanisms of horizontal gene transfer.
D.10 Educational activities
COBISS.SI-ID: 4849016Prof. Dr. Ines Mandic-Mulec was awarded with Zois's award for significant scientific achievements in the field of microbiology in 2017 and participated in the TV program ‘’Odmevi’’ on Slovenian national television. Prof. Dr. Mandic-Mulec is a world-renowned expert in the field of social microbiolgy, biofilms and other research on Bacillus subtilis, an important industrial micro-organism and also plant growth promoting organism. She discovered the phenomenon of the kin recognition, molecular mechanism of this recognition and the diversity of Bacillus communication systems. Prof. Dr. Mandić-Mulec also made a key contribution to the development of microbiology of soil and aquatic ecological systems in Slovenia. She explored how different environmental factors (e.g., nutrients, pollutants) affect the phylogenetic composition and function of microbial communities in connection with nutrient contraction. In Slovenia, she was the first that related the influence of soil drying with microbial activity and the associated greenhouse gas release. Scientific work of prof. dr. Mandic-Mulec is distinguished by top quality, high international rating and numerous invited lectures at conferences in renowned universities. In the TV program ‘’Odmevi’’, she presented her view of science on social microbiology and the understanding of bacterial interactions. She underlined the importance of cooperation and international funding opportunities in science.
E.01 National awards
COBISS.SI-ID: 4878712