title: Coagulase-negative staphylococci (CoNS) isolated from ready-to-eat food of animal origin--phenotypic and genotypic antibiotic resistance.
abstract: The aim of this work was to study the pheno- and genotypical antimicrobial resistance profile of coagulase negative staphylococci (CoNS) isolated from 146 ready-to-eat food of animal origin (cheeses, cured meats, sausages, smoked fishes). 58 strains were isolated, they were classified as Staphylococcus xylosus (n = 29), Staphylococcus epidermidis (n = 16); Staphylococcus lentus (n = 7); Staphylococcus saprophyticus (n = 4); Staphylococcus hyicus (n = 1) and Staphylococcus simulans (n = 1) by phenotypic and genotypic methods. Isolates were tested for resistance to erythromycin, clindamycin, gentamicin, cefoxitin, norfloxacin, ciprofloxacin, tetracycline, tigecycline, rifampicin, nitrofurantoin, linezolid, trimetoprim, sulphamethoxazole/trimethoprim, chloramphenicol, quinupristin/dalfopristin by the disk diffusion method. PCR was used for the detection of antibiotic resistance genes encoding: methicillin resistance--mecA; macrolide resistance--erm(A), erm(B), erm(C), mrs(A/B); efflux proteins tet(K) and tet(L) and ribosomal protection proteins tet(M). For all the tet(M)-positive isolates the presence of conjugative transposons of the Tn916-Tn1545 family was determined. Most of the isolates were resistant to cefoxitin (41.3%) followed by clindamycin (36.2%), tigecycline (24.1%), rifampicin (17.2%) and erythromycin (13.8%). 32.2% staphylococcal isolates were multidrug resistant (MDR). All methicillin resistant staphylococci harboured mecA gene. Isolates, phenotypic resistant to tetracycline, harboured at least one tetracycline resistance determinant on which tet(M) was most frequent. All of the isolates positive for tet(M) genes were positive for the Tn916-Tn1545 -like integrase family gene. In the erythromycin-resistant isolates, the macrolide resistance genes erm(C) or msr(A/B) were present. Although coagulase-negative staphylococci are not classical food poisoning bacteria, its presence in food could be of public health significance due to the possible spread of antibiotic resistance.
authors.affiliation: Chair of Industrial and Food Microbiology, Department of Food and Industrial Microbiology, Faculty of Food Science, University of Warmia and Mazury, Plac Cieszyński 1, 10-726 Olsztyn, Poland. Electronic address: wioleta.chajecka@uwm.edu.pl.
authors.forename: Wioleta
authors.initials: W
authors.lastname: Chajęcka-Wierzchowska
authors.affiliation: Chair of Industrial and Food Microbiology, Department of Food and Industrial Microbiology, Faculty of Food Science, University of Warmia and Mazury, Plac Cieszyński 1, 10-726 Olsztyn, Poland. Electronic address: anna.zadernowska@uwm.edu.pl.
authors.forename: Anna
authors.initials: A
authors.lastname: Zadernowska
authors.affiliation: Chair of Industrial and Food Microbiology, Department of Food and Industrial Microbiology, Faculty of Food Science, University of Warmia and Mazury, Plac Cieszyński 1, 10-726 Olsztyn, Poland.
authors.forename: Beata
authors.initials: B
authors.lastname: Nalepa
authors.affiliation: Chair of Industrial and Food Microbiology, Department of Food and Industrial Microbiology, Faculty of Food Science, University of Warmia and Mazury, Plac Cieszyński 1, 10-726 Olsztyn, Poland.
authors.forename: Magda
authors.initials: M
authors.lastname: Sierpińska
authors.affiliation: Chair of Industrial and Food Microbiology, Department of Food and Industrial Microbiology, Faculty of Food Science, University of Warmia and Mazury, Plac Cieszyński 1, 10-726 Olsztyn, Poland.
authors.forename: Łucja
authors.initials: Ł
authors.lastname: Łaniewska-Trokenheim
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics; D002417:Cattle; D002611:Cheese / Q000382:microbiology*; D003030:Coagulase / Q000235:genetics / Q000378:metabolism; D024901:Drug Resistance, Multiple, Bacterial; D057140:Fast Foods / Q000382:microbiology*; D005399:Fishes; D005838:Genotype; D008461:Meat Products / Q000382:microbiology*; D010641:Phenotype; D013210:Staphylococcus / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D013552:Swine
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D003030:Coagulase
keywords: Antibiotic resistance; Coagulase-negative staphylococci; Ready-to-eat food