20.500.12556/DKUM-84029 Clostridioides difficile in bakterije iz skupine Bacillus cereus v iztrebkih voluharic Clostridioides difficile and Bacillus cereus group in vole fecal samples Bacillus cereus je Gram-pozitivna aerobna sporogena bakterija. Različni sevi B. cereus so si tako fenotipsko, kot v sekvencah genomov precej podobni z nekaterimi drugimi vrstami rodu Bacillus, zato jih skupaj uvrščamo v skupino B. cereus. Zaradi širokega temperaturnega optimuma je vsesplošno razširjena v naravnem okolju in naseljuje različne ekološke niše. Primerno okolje za rast in razvoj predstavljajo tudi prebavila žuželk in sesalcev. B. cereus povzroča tudi okužbe pri ljudeh. Pri okužbah so pomembni sevi, ki imajo gene za emetični in/ali diarealni toksin. Bakterija Clostridioides difficile je Gram-pozitivna oportunistična anaerobna bakterija, ki povzroča bolezni tako pri ljudeh, kot živalih. Razširjena je po vsem svetu. Okužba s C. difficile povzroča vnetje debelega črevesa in drisko, vendar samo pri osebah s porušeno črevesno mikrobioto. Razen pri človeku, jo najdemo v prebavilih mnogih živalskih vrst, tudi pri glodavcih. Ker so glodavci in žužkojedi v bližini človeških bivališč precej pogosti, prebavila voluharic pa predstavljajo rezervoar bakterije B. cereus, smo v nalogi ugotavljali ali in v kolikšnem deležu so te bakterije prisotne v prebavilih voluharic, v naši geografski regiji. Ugotovili smo, da je pojavnost bakterije B. cereus visoka. Iz 20 pobranih vzorcev smo izolirali 54 bakterijskih sevov B. cereus. Od tega smo jih 41 identificirali kot B. cereus sensu lato in 13 kot B. cereus sensu stricto. Seve identificirane kot B. cereus in sorodne seve (skupine B. cereus) smo testirali na prisotnost diarealnega ali emetičnega toksina. V večini sevov (39 izmed 45 testiranih) je bil prisoten diarealni toksin, ki se je pojavil pri 38 izoliranih sevih, medtem, ko pri nobenem sevu nismo zaznali emetičnega toksina. Poleg tega smo iskali tudi bakterijo C. difficile, ki je bila v Sloveniji že opisana pri različnih živalih, prsti in v vodi, ne pa še pri glodavcih. Bakterijo C. difficile smo potrdili samo v enem izmed vzorcev fecesa. Bacillus cereus is a Gram-positive aerobic sporogenic bacterium. Both phenotypically and in genome sequences, B. cereus strains are quite similar to some other species of the Bacillus genus, so they are grouped together in the B. cereus group. Due to its wide temperature optimum, it is widespread in the natural environment and found in various ecological niches. The digestive tracts of insects and mammals also represents a suitable environment for growth and development. B. cereus can cause infections in humans. Strains with genes for emetic and/or diarrhea toxin are important in food associated infections. Clostridioides difficile is a Gram-positive opportunistic anaerobic bacterium that causes disease in both humans and animals. C. difficile infection causes inflammation of the colon and diarrhea, but only in people with disrupted gut microbiota. Apart from humans, C. difficile is found in the digestive tracts of many animal species, including rodents. Since rodents and insectivores are quite common in the vicinity of human habitats, and the guts of voles represent a reservoir of B. cereus bacteria, we determined whether and in what proportion these bacteria are present in the guts of voles in our geographical region. We found that the incidence of B. cereus bacteria is high. We isolated 54 bacterial strains of B. cereus from 20 collected samples. Of these, we identified 41 as B. cereus sensu lato and 13 as B. cereus sensu stricto. Strains identified as B. cereus and related strains (B. cereus group) were tested for the presence of diarrheal or emetic toxin. Diarrheal toxin was present in 39 out of 54 tested strains, while no emetic toxin was detected in any of the strains. Apart from this, we also looked for the bacterium C. difficile, which was already described in Slovenia in various animals, soil and water, but not yet in rodents. The bacterium C. difficile was detected in only one of the faeces samples. Clostridioides difficile skupina Bacillus cereus voluharice prebavni trakt spore toksini Clostridioides difficile Bacillus cereus group voles intestine spores toxins true true false [U. Krautberger Balažić] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2023-03-30 18:45:35 2023-04-13 09:45:50 2023-04-14 03:08:47 0000-00-00 00:00:00 2023 0 Maribor 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 579.8(043.2) 148564995 MAG_Krautberger_Balazic_Ursulla_2023.pdf MAG_Krautberger_Balazic_Ursulla_2023.pdf 1 D1562F78C55ABF21182EF8E6C8E374C6 58e4a2787b10a383990c869efccf00499023d7cf2a1204e82a103dcc76586009 d201c82e-cf27-11ed-bf67-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=166431 Fakulteta za naravoslovje in matematiko 0 0 0