Odpornost ocetnokislinskih bakterij proti izbranim antibiotikom in šibkim organskim kislinam

magistrsko delo

Lora Klanfar (Avtor), Janja Trček (Mentor), Jure Škraban (Komentor)

Povzetek

V okviru magistrskega dela smo pri 34 izbranih sevih ocetnokislinskih baterij iz rodov Komagataeibacter in Acetobacter preučevali odpornost proti naslednjim antibiotikom: ampicilinu, kloramfenikolu, ciprofloksacinu, eritromicinu, gentamicinu in trimetoprimu. Odpornost smo ocenili s pregledovanjem rasti okrog diskov, prepojenih z znanimi koncentracijami antibiotikov. Šest sevov je bilo odpornih proti vsem testiranim antibiotikom, 16 sevov proti petim antibiotikom, 11 sevov proti štirim antibiotikom in en sev proti trem antibiotikom. V nadaljevanju smo v genomskih sekvencah preiskanih referenčnih sevov poiskali gene, ki potencialno kodirajo proteine za odpornost proti testiranim antibiotikom. Pri tem smo uporabili bazo CARD s poznanimi geni za odpornost proti antibiotikom. Najpogostejša funkcija genov, ki smo jih identificirali, je bila črpalka za transport antibiotikov iz celice. Poleg odpornosti proti antibiotikom smo pri štirih sevih iz rodu Komagataeibacter in štirih sevih iz rodu Acetobacter preiskali tudi odpornost proti ocetni in citronski kislini s testiranjem sposobnosti rasti v tekočem gojišču v prisotnosti 1 % etanola in različnih koncentracij ene izmed obeh kislin. Najvišjo odpornost proti ocetni kislini (4,5 %) smo ugotovili pri sevu Acetobacter pomorum LMG 18848T in Acetobacter pasteurianus T6K1, najmanjšo (1,5 %) pa za sev Acetobacter aceti LMG 1504T. Največjo odpornost proti citronski kislini (3,5 %) smo ugotovili za sev Komagataeibacter sp. AV429, najmanjšo (0,69 %) pa za seve Acetobacter pomorum LMG 18848T, Acetobacter pasteurianus LMG 1262T in Acetobacter pasteurianus T6K1. Z namenom, da bi ugotovili stabilnost genoma seva Komagataeibacter sp. AV382 po precepljanju na gojišču RAE v prisotnosti 1 % etanola in 1 % ocetne kisline, smo po šestih mesecih precepljanja (dvakrat tedensko) po sekvencirali genom in ga primerjali z genomsko sekvenco tega seva pred precepljanjem. Z bioinformatskim orodjem MAUVE smo identificirali regijo, za katero se je zdelo, da se je prestavila, a z uporabljenimi začetnimi oligonukleotidi v reakciji PCR, tega nismo uspeli dokazati.

Ključne besede

magistrska dela;ocetnokislinske bakterije;odpornost proti antibiotikom;odpornost proti šibkim organskim kislinam;stabilnost genoma;

Podatki

Jezik:	Slovenski jezik
Leto izida:	2020
Tipologija:	2.09 - Magistrsko delo
Organizacija:	UM FNM - Fakulteta za naravoslovje in matematiko
Založnik:	[L. Klanfar]
UDK:	579:575(043.2)
COBISS:	24976387
Št. ogledov:	703
Št. prenosov:	99
Ocena:	0 (0 glasov)
Metapodatki:

Ostali podatki

Sekundarni jezik:	Angleški jezik
Sekundarni naslov:	Resistance of acetic acid bacteria against selected antibiotics and weak organic acids
Sekundarni povzetek:	The objective of this master thesis was to screen among 34 selected strains of acetic acid bacteria from the genera Komagataeibacter and Acetobacter for their resistance against the following antibiotics: ampicillin, chloramphenicol, ciprofloxacin, erythromycin, gentamicin and trimethoprim. Resistance was evaluated by examining growth around discs, which were soaked with known concentrations of antibiotics. Six strains were resistant to all tested antibiotics, 16 strains against five antibiotics, 11 strains against four antibiotics and one strain against three antibiotics. Next, we searched for genes that could potentially encode proteins for resistance against tested antibiotics in genomic sequences of the investigated reference strains. We used CARD base with known genes for antibiotics resistance. The most common function of the genes, which we have identified, was antibiotic efflux pump. In the addition to antibiotic resistance, we have also screened four strains from the genera Komagataeibacter and four strains from the genera Acetobacter for their resistance against acetic and citric acid, by testing the ability to grow in liquid medium in the presence of 1 % ethanol and different concentrations of one of the two acids. The highest resistance against acetic acid (4.5 %) was found in strain Acetobacter pomorum LMG 18848T and Acetobacter pasteurianus T6K1 and the lowest (1.5 %) in strain Acetobacter aceti LMG 1504T. The highest resistance against citric acid (3.5 %) was found in strain Komagataeibacter sp. AV429 and the lowest (0.69 %) in strains Acetobacter pomorum LMG 18848T, Acetobacter pasteurianus LMG 1262T in Acetobacter pasteurianus T6K1. In order to determine genome stability of the strain Komagataeibacter sp. AV382 after inoculation on RAE medium in the presence of 1 % ethanol and 1 % acetic acid, we sequenced the genome after six months of precultering twice a week and compared it with genomic sequence of that strain before starting with preculturing. With bioinformatics tool MAUVE we identified a region that appeared to shift, but with using specific primers in PCR reaction we failed to prove that.
Sekundarne ključne besede:	master theses;acetic acid bacteria;antibiotic resistance;weak organic acid resistance;genome stability;
Vrsta dela (COBISS):	Magistrsko delo/naloga
Komentar na gradivo:	Univ. v Mariboru, Fak. za naravoslovje in matematiko, Oddelek za biologijo
Strani:	X, 103 f.
ID:	11844385