In total, 84 yeast strains (originated from water, plants, fruits and soil) were selected for MALDI-TOF biotyping. All strains were cultivated on malt agar and YPD medium. Samples for biotyping were processed according to methods of Bruker Daltonik GmbH company, Institute of Chemistry of SAS and combination of these methods. Single strains were identified based on the analysis of intracellular ribozomal proteins using MALDI-TOF mass spectrometry. In case of ambiguous results, the DNA was isolated and the D1/D2 26S rRNA domain sequencing was performed. The strain identification was carried out by comparing its mass spectra with spectra of sequenced strains using MALDI Biotyper 3.0 software. The mutual similarity of strains was considered by score value, which was the result of the analysis. In total, 18 strains from 84 were previously sequenced and used as model strains for comparison with unknown isolates. Altogether 51 strains were definitely taxonomically categorized into 18 phylogenetic groups at the species level. The MALDI-TOF biotyping was repeated for overall 6 strains because of ambiguity of results. The taxonomic classification of 15 strains was not clearly determined and, therefore, these strains were suggested for D1/D2 26S rRNA domain sequencing. It was not possible to identify one strain, based on the results of sequencing, therefore, the DNA isolation was repeated. In the case of 8 strains, the results were identical with originally designed taxonomic classification. Conversely, the remaining 6 strains were identified as species. For 20 selected strains the basic characteristics were determined using microbiological methods. The shape of colonies growing on solid medium and appearance of cultures in liquid medium was assessed. Furthermore, the radial growth constant and the presence of urease were determined. Finally the microscopic observation of cells and the fermentation test for carbohydrate substrates were performed.
Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:295643 |
Date | January 2017 |
Creators | Jurnečková, Alena |
Contributors | Dudášová,, Hana, Stratilová, Eva |
Publisher | Vysoké učení technické v Brně. Fakulta chemická |
Source Sets | Czech ETDs |
Language | Czech |
Detected Language | English |
Type | info:eu-repo/semantics/masterThesis |
Rights | info:eu-repo/semantics/restrictedAccess |
Page generated in 0.0018 seconds