20.500.12556/DKUM-89188 Hruškov in jabolčno-grozdni kis: vira novih bakterijskih vrst iz rodov Acetobacter, Novacetimonas in Komagataeibacter magistrsko delo Pear and apple-grape vinegar: sources of novel bacteria species of the genera Acetobacter, Novacetimonas and Komagataeibacter Bakterijske vrste iz rodov Acetobacter, Novacetimonas, Gluconacetobacter in Komagataeibacter imajo številne industrijsko zanimive lastnosti, npr. učinkovito proizvajajo nanocelulozo, vodotopne zunajcelične heteropolisaharide iz skupine acetanov ter različne kisline. Bakterijska nanoceluloza je biomaterial s široko uporabno vrednostjo v medicini, kozmetiki, živilstvu in okoljevarstvu. Acetani so zaradi svojih edinstvenih viskoelastičnih lastnosti uporabni kot zgoščevalci in emulgatorji v živilstvu in farmaciji. Prisotnost ustreznih kislin je v živilski industriji pomembna za proizvodnjo kombuče, kisa in določenih vrst piva. Industrija se vedno bolj zateka k naravnim virom ter išče nove seve z optimalnimi lastnostmi za posamezne proizvode. Vsled temu so izolacija, karakterizacija in ohranjanje novih sevov ocetnokislinskih bakterij pomembni za oblikovanje ustreznih zbirk tovrstnih industrijsko zanimivih bakterij. V tej raziskavi smo z metagenomsko analizo pomnožkov medgenskih regij 16S‒23S rDNA preiskali ocetnokislinsko bakterijsko združbo iz dveh do sedaj še neraziskanih vrst kisa, t. j. hruškov in jabolčno-grozdni kis. Poleg že znanih vrst ocetnokislinskih bakterij, kot so Komagataeibacter sucrofermentans, Acetobacter lovaniensis, Acetobacter syzygii, Gluconacetobacter liquefaciens, Gluconobacter albidus in Komagataeibacter europaeus, ki so bile zastopane v več kot 0,1 % deležu, smo v obeh vrstah odkrili več potencialno novih vrst, večino iz rodu Acetobacter. Zastopanost posamezne potencialno nove vrste je bila do 28,9 %. Da bi nove vrste izolirali, smo pripravili redčine kisa, jih nacepili na kompleksno gojišče RAE ter iz morfološko različnih kolonij pridobili več izolatov. V nadaljevanju smo se osredotočili na karakterizacijo štirih izoliranih sevov: Komagataeibacter sp. nov. Hr1, Acetobacter sp. nov. Hr2, Gluconacetobacter sp. nov. Hr-1-5 in Novacetimonas sp. nov. Jurk4. Sevom smo preiskali genome s tehnologijo Illumina in Nanopore ter okarakterizirali njihov potencial za sintezo celuloze in acetanov, ketoglukonskih kislin, rastne karakteristike v kompleksnih gojiščih ter ugotavljali rezistenco proti klinično relevantnim antibiotikom. Bacterial species from genera Acetobacter, Novacetimonas, Gluconacetobacter and Komagataeibacter have many industrially interesting properties, such as the production of bacterial nanocellulose, water-soluble acetan-like extracellular heteropolysaccharides and different acids. Bacterial nanocellulose is a biomaterial with broad applicative value in medicine, cosmetics, food industry and environmental conservation. Due to their unique viscoelastic properties, acetans are useful as thickeners and emulsifiers in food industry and pharmacy. The presence of adequate acids is important in the food industry for producing kombucha, vinegar and some types of beer. The industry is increasingly turning to natural sources and looking for new strains with optimal properties for specific products. Therefore, isolation, characterisation and conservation of new acetic acid bacteria species are important for designing culture collections of industrially important bacteria. In this study, we used the metagenomics of the amplified 16S-23S rDNA internal transcribed spacer (ITS) region to analyze the acetic acid bacteria consortia of two previously unexplored types of vinegar: pear vinegar and apple-grape vinegar. Besides already known species of acetic acid bacteria, such as Komagataeibacter sucrofermentans, Acetobacter lovaniensis, Acetobacter syzygii, Gluconacetobacter liquefaciens, Gluconobacter albidus and Komagataeibacter europaeus, that were present in more than 0,1 %, we discovered some potentially novel species, most from genera Acetobacter. The presence of individual potentially novel species was up to 28,9 %. In order to isolate these new strains, we prepared dilutions of vinegar, inoculated them onto a complex RAE medium, and obtained multiple isolates from morphologically distinct colonies. Later on, we focused on the characterisation of four novel strains: Komagataeibacter sp. nov. Hr1, Acetobacter sp. nov. Hr2, Gluconacetobacter sp. nov. Hr-1-5 and Novacetimonas sp. nov. Jurk4. We examined the genomes of these strains using Illumina and Nanopore technologies, and characterised their potential for cellulose and acetan synthesis, ketogluconic acid production, growth characteristics in complex RAE medium and resistance to clinically relevant antibiotics. Hruškov kis jabolčno-grozdni kis nove vrste ocetnokislinskih bakterij ocetnokislinske bakterije. Pear vinegar apple-grape vinegar novel acetic acid bacteria species acetic acid bacteria. true true false [B. Karničnik] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2024-06-24 13:14:38 2024-07-08 13:37:59 2024-07-09 03:49:54 0000-00-00 00:00:00 2024 0 Maribor 0 Maribor X, 96 f. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 579.61(043.2) 201037827 MAG_Karnicnik_Bernarda_2024.pdf MAG_Karnicnik_Bernarda_2024.pdf 1 FF2AA9B5D28A7D72461D5EC1ED0CD1EE 1cc58dc82c6f84060a6c42f511e6de8338e6a1f14c8432bc6d2c11e25d62150f 68d7e86d-321d-11ef-a99d-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=180738 Fakulteta za naravoslovje in matematiko 0 0 0