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In the presented work identification of microorganisms isolated from various types of honeys was performed. Martix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rDNA sequencing were applied to study environmental bacteria strains.With both approches, problematic spore-forming Bacillus spp , but also Staphylococcus spp ., Lysinibacillus spp ., Micrococcus spp . and Brevibacillus spp were identified. However, application of spectrometric technique allows for an unambiguous distinction between species/species groups e.g. B . subtilis or B . cereus groups. MALDI TOF MS and 16S rDNA sequencing allow for construction of phyloproteomic and phylogenetic trees of identified bacterial species. Furthermore, the correlation beetween physicochemical properties, geographical and botanical origin and the presence bacterial species in honey samples were investigated.

Rapid detection and identification of microorganisms is a challenging and important aspect in a wide range of fields, from medical to industrial, affecting human lives. Unfortunately, classical methods of microorganism identification are based on time-consuming and labor-intensive approaches. Screening techniques require the rapid and cheap grouping of bacterial isolates; however, modern bioanalytics demand comprehensive bacterial studies at a molecular level. Modern approaches for the rapid identification of bacteria use molecular techniques, such as 16S ribosomal RNA gene sequencing based on polymerase chain reaction or electromigration, especially capillary zone electrophoresis and capillary isoelectric focusing. However, there are still several challenges with the analysis of microbial complexes using electromigration technology, such as uncontrolled aggregation and/or adhesion to the capillary surface. Thus, an approach using capillary electrophoresis of microbial aggregates with UV and matrix-assisted laser desorption ionization time-of-flight MS detection is presented.

The submitted work assumes that the abundance and diversity of endophytic and rhizosphere microorganisms co-existing with the halophytic plant Aster tripolium L. growing in a salty meadow in the vicinity of a soda factory (central Poland) represent unique populations of cultivable bacterial strains. Endophytic and rhizosphere bacteria were (i) isolated and identified based on 16S rDNA sequences; (ii) screened for nifH and acdS genes; and (iii) analyzed based on selected metabolic properties. Moreover, total microbial biomass and community structures of the roots (endophytes), rhizosphere and soil were evaluated using a cultivation-independent technique (PLFA) to characterize plant-microbial interactions under natural salt conditions. The identification of the isolated strains showed domination by Gram-positive bacteria (mostly Bacillus spp.) both in the rhizosphere (90.9%) and roots (72.7%) of A. tripolium. Rhizosphere bacterial strains exhibited broader metabolic capacities, while endophytes exhibited higher specificities for metabolic activity. The PLFA analysis showed that the total bacterial biomass decreased in the following order (rhizosphere

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