Molekularna serotipizacija sojeva bakterije Salmonella izoliranih iz pilećeg mesa za prodaju, na temelju in silico višestrukog PCR-a, određivanja ESBL-a i gena kolistin rezistencije mcr-1 do -5

Salmonella spp. are zoonotic pathogenic agents that cause important infections in humans and animals. They are the most common foodborne pathogens after Campylobacter spp. worldwide. The aim of this study was to determine the phenotypic and genotypic extended-spectrum β-lactamase (ESBL) and colistin resistance of 67 Salmonella spp. isolated from retail chicken meats between May and December 2016, and stored in the culture collection of Ataturk University, Faculty of Veterinary Medicine, Department of Microbiology. The isolates were serotyped using multiplex polymerase chain reaction (mPCR). The serovar distribution of strains was 74.6% S. Infantis, 16.4% S. Enteritidis, 3.0% S. Arizonae, 3.0% S. Dublin, 1.5% S. Gallinarum and 1.5% S. Indica. Of the 67 strains, 20 (29.9%) were ESBL- positive. The main types of β-lactamase identified were blaCTX-M-1, blaCTX-M-8-25, blaSHV and blaTEM. Four isolates were found to be phenotypically colistin-resistant. These isolates did not carry mobilised colistin resistance (mcr) genes 1 to 5. In this study, both genotypically ESBL-producing and phenotypically colistin-resistant Salmonella strains were found. We revealed that ESBL-producing Salmonella strains have dramatically increased over the years, especially when compared with previously reported chicken meat Salmonella strains in Turkey. The increase in Salmonella strains, particularly ESBL producers and the colistin resistant, is of great concern for selected antimicrobial therapy in human infections. Hence, epidemiological information and monitoring systems are extremely important in controlling Salmonella infections in public health services.Salmonella spp. zoonotski su patogeni koji uzrokuju infekcije u ljudi i životinja. Na globalnoj su razini najčešći patogeni koji se prenose hranom poslije bakterija Campylobacter spp. Cilj ovog istraživanja bio je fenotipski i genotipski odrediti β-laktamaze proširenog spektra (ESBL) i otpornost na kolistin 67 sojeva bakterija Salmonella spp. izoliranih iz pilećeg mesa za prodaju od svibnja do prosinca 2016. i pohranjenih u kulturama na Odsjeku za mikrobiologiju Fakulteta veterinarske medicine na Sveučilištu Ataturk. Izolati su serotipizirani primjenom višestruke lančane reakcije polimerazom (mPCR). Distribucija serovara bila je: 74,6 % za S. Infantis, 16,4 % za S. Enteritidis, 3,0 % za S. Arizonae, 3,0 % za S. Dublin, 1,5 % za S. Gallinarum i 1,5 % za S. Indica. Od 67 sojeva njih je 20 (29,9 %) bilo pozitivno na ESBL. Glavni identificirani tipovi β-laktamaza bili su: blaCTX-M-1, blaCTX-M-8-25, blaSHV i blaTEM. Četiri izolata bila su fenotipski otporna na kolistin. Ovi izolati nisu sadržavali aktivne gene rezistencije na kolistin (mcr) 1 do 5. U ovom su istraživanju nađeni i sojevi salmonele koji su genotipski proizvodili ESBL i sojevi fenotipski otporni na kolistin. Sojevi salmonele koji proizvode ESBL s godinama su se znatno povećali, posebno u usporedbi s prethodnim izvješćima o sojevima salmonele u mesu pilića u Turskoj. Porast sojeva salmonele, osobito onih koji proizvode ESBL i onih koji su otporni na kolistin, zabrinjava zbog antimikrobnog liječenja infekcija u ljudi. Zbog toga su u kontroli infekcija salmonelama u javnome zdravstvu iznimno važni epidemiološki podaci i sustavi praćenja

Detekcija nekoliko faktora virulencije, rezistencije na antibiotike i filogenetskih odnosa izolata E. coli poreklom od krava sa mastitisom

Cow mastitis caused by Escherichia coli (E. coli) exhibits various local and systemic clinical signs at varying degrees of severity. The aim this study was to elucidate the virulence properties, antibiotic resistance and phylogenetics of 56 E. coli strains. Of all the studied strains, 12 were positive for hemolytic properties and 38 were positive for biofilm production. Additionally, 55 of the strains were positive for multiple resistances in bacteriological tests. PCR analysis revealed that 42 strains carried the traT gene, 20 strains had the shiga toxin gene (stx1-stx2), and 8 strains carried the intimin gene (eae), but all strains were negative for aerobactin gene (aer). All strains encoding shiga toxin genes were also positive for stx1, but only 4 strains were positive for stx2. There were no significant differences in virulence genes between antibiotic-resistant and antibiotic-susceptible strains. The random amplifi ed polymorphic DNA-polymerase chain reaction patterns revealed the existence of 13 main groups with 4 subgroups of E. coli. In this study, E. coli strains causing intramammary infections and originating from various sources might show resistance against common antibiotics. Pathogenity of E. coli that cause clinical mastitis, and prognosis of the infection might be predicted by obtaining the traTMastitis kod krava, izazvan bakterijom Escherichia coli (E. coli) ima različite lokalne i sistemske kliničke simptome čiji stepen izraženosti značajno varira. Cilj ispitivanja je bio da se ustanove virulentni faktori, rezistencija na antibiotike kao i fi logeneza 56 sojeva E. coli. Od svih ispitivanih sojeva, 12 je bilo pozitivno na hemolitičku aktivnost a 38 je proizvodilo biofi lm. Pored ovoga, 55 sojeva je bilo pozitivno na multiplu rezistenciju u bakteriološkim testovima. PCR analiza je pokazala da je 42 soja posedovalo traT gen, 20 sojeva je posedovalo shiga toksin gen (stx1-stx2), a 8 sojeva je posedovalo intimin gen (eae), ali su svi ispitivani sojevi bili negativni na aerobaktin gen (aer). Svi sojevi koji su posedovali shiga toksin gene bili su pozitivni i na stx1, ali je samo 4 soja bilo pozitivno na stx2 gen. Nije bilo značajnih razlika u genima virulencije između antibiotik-rezistentnih i antibiotik-osetljivih sojeva. Polimorfna DNK-PCR je pokazala da postoji 13 osnovnih grupa sa 4 podbrupe E. coli. U ovoj studiji, E. coli sojevi Cengiz et al. 425 koji su izazivali intramamarne infekcije i koji su poticali iz različitih izvora pokazali su razistenciju na uobičajene antibiotike. Patogenost E. coli koja izaziva klinčke forme mastitisa kao i prognoza infekcije može da se predvidi na osnovu podataka o prisustvu traT gena. Pored ovoga, rezistencija na antibiotike treba da se ispita na genetskoj osnovi u cilju detekcije povezanosti između faktora virulencije i rezistencije na antibiotike. U terenskim uslovima, razvoj rezistencije na antibiotike je osnovni uzrok neuspešne terapije mastitisa. Može da se zaključi da je u stadu neophodno obavljati monitoring profi la rezistencije na antibiotike uz primenu efi kasnih antibiotika

Distribution of CRISPR Types in Fluoroquinolone-Resistant Campylobacter jejuni Isolates

To aid development of phage therapy against Campylobacter, we investigated the distribution of the clustered regularly interspaced short palindromic repeats (CRISPR) systems in fluoroquinolone (FQ)-resistant Campylobacter jejuni. A total of 100 FQ-resistant C. jejuni strains from different sources were analyzed by PCR and DNA sequencing to determine resistance-conferring mutation in the gyrA gene and the presence of various CRISPR systems. All but one isolate harbored 1–5 point mutations in gyrA, and the most common mutation was the Thr86Ile change. Ninety-five isolates were positive with the CRISPR PCR, and spacer sequences were found in 86 of them. Among the 292 spacer sequences identified in this study, 204 shared 93–100% nucleotide homology to Campylobacter phage D10, 44 showed 100% homology to Campylobacter phage CP39, and 3 had 100% homology with Campylobacter phage CJIE4-5. The remaining 41 spacer sequences did not match with any phages in the database. Based on the results, it was inferred that the FQ-resistant C. jejuni isolates analyzed in this study were potentially resistant to Campylobacter phages D10, CP39, and CJIE4-5 as well as some unidentified phages. These phages should be excluded from cocktails of phages that may be utilized to treat FQ-resistant Campylobacter

Evaluation of Antimicrobial Resistance in Staphylococcus Spp. Isolated from Subclinical Mastitis in Cows

The objective of this study was to determine the antibiotic resistance in different Staphylococcus isolates using conventional and molecular methods. A total of 61 subclinical mastitis isolates of Staphylococci were evaluated for oxacillin, erythromycin, tetracycline, nitrocefin, and cefoxitin using the Kirby-Bauer disc diffusion method. The same isolates were also subjected to the multiplex PCR technique to detect mecA, femA and ermA, ermC, tetK, and tetM genes. Of the isolates, (Staphylococcus aureus, n=34 and coagulase negative Staphylococcus (CoNS), n=27) 26, 29, and 8 were resistant to erythromycin, tetracycline, and oxacillin, respectively in phenotypical evaluation. The genotypical evaluation indicated that of the strains, 34 carried erm genes in erythromycin-resistant strains and 10 carried tet genes in tetracycline-resistant strains. Agreement rates between genotypic and phenotypic evaluation for erythromycin, tetracycline and methicillin were 57, 65.5 and 89% respectively. Data suggest that phenotypical methods should be accompanied by genotypical methods to establish antibacterial resistance accurately, which would enhance treatment efficiency. (C) 2015 PVJ. All rights reserve