Antibiotic resistance of coagulase-negative staphylococci associated with food and used in starter cultures.
The resistance of 330 coagulase-negative staphylococci (CNS) associated with food or used in starter cultures and belonging to the species Staphylococcus carnosus, Staphylococcus condimenti, Staphylococcus piscifermentans, Staphylococcus equorum, Staphylococcus succinus and Staphylococcus xylosus, against 21 antibiotics was determined using the disk diffusion method. The incidence and number of resistances was found to be species and source of isolation dependent. Most strains of S. equorum (63%), S. succinus (90%) and S. xylosus (95%) exhibited resistances against up to seven antibiotics, whereas only few strains of S. carnosus (12%) and S. piscifermentans (27%) were antibiotic resistant. Resistances to lincomycin, penicillin, fusidic acid, oxacillin, ampicillin and tetracycline were predominant. Among strains of S. xylosus, the incidence of resistance ranged from 22% for tetracycline up to 69% for penicillin. Concerning the source of isolation, resistances were often determined in strains of S. equorum, S. succinus and S. xylosus isolated from cheese (87%) and sausage (83%), and strains of S. xylosus obtained from meat starter cultures (93%). Remarkably, all CNS were sensitive to the clinically important antibiotics chloramphenicol, clindamycin, cotrimoxazol, gentamicin, kanamycin, linezolid, neomycin, streptomycin, synercid and vancomycin. The phenotypic resistances to beta-lactam antibiotics, lincomycin and tetracycline were verified by PCR amplification and could be traced back to the genes blaZ, lnuA and tetK, respectively. This study permitted a comprehensive insight into the incidence of antibiotic resistances in food-associated CNS.
Resch
Marion
M
University of Hohenheim, Institute of Food Science and Biotechnology, Section Food Microbiology, Garbenstrasse 28, D-70599 Stuttgart, Germany.
Nagel
Verena
V
Hertel
Christian
C
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003030:Coagulase / Q000378:metabolism; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D005516:Food Microbiology; D008826:Microbial Sensitivity Tests; D012335:RNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D013045:Species Specificity; D013202:Staphylococcal Food Poisoning / Q000382:microbiology* / Q000517:prevention & control; D013210:Staphylococcus / Q000145:classification / Q000187:drug effects* / Q000201:enzymology
D000900:Anti-Bacterial Agents; D003030:Coagulase; D004269:DNA, Bacterial; D012335:RNA, Ribosomal