title: Resistance to β-lactams in bacteria isolated from different types of Portuguese cheese.
abstract: The purpose of this study was to investigate the presence of beta-lactam-resistant bacteria in six different types of Portuguese cheese. The numbers of ampicillin resistant (AMP(r)) bacteria varied from 4.7 x 10(2) to 1.5 x 10(7) CFU/g. Within 172 randomly selected beta-lactam-resistant bacteria, 44 resistant phenotypes were found and 31.4% were multidrug resistant. The majority (85%) of the isolates identified belonged to the Enterobacteriaceae family. The presence of the bla(TEM) gene was detected in 80.9% of the tested isolates. The results suggest that without thermal processing of the milk and good hygienic practices, cheese may act as a vehicle of transfer of beta-lactam-resistant bacteria to the gastrointestinal tract of consumers.
authors.affiliation: Laboratório de Microbiologia, CBAA/DBEB, Instituto Superior de Agronomia, Technical University of Lisbon, Tapada da Ajuda 1349-017 Lisbon, Portugal.|Ciências Químicas e das Biomoléculas, Escola Superior de Tecnologia de Saúde do Porto, Instituto Politécnico do Porto, Praça do Coronel Pacheco, No. 15, 4050-453 Porto, Portugal.|Ciências Exactas e do Ambiente, Sector de Biologia e Ecologia, Escola Superior Agrária, Instituto Politécnico de Coimbra, Bencanta, 3040-316 Coimbra, Portugal.
authors.forename: Paula
authors.initials: P
authors.lastname: Amador
authors.affiliation: Ciências Químicas e das Biomoléculas, Escola Superior de Tecnologia de Saúde do Porto, Instituto Politécnico do Porto, Praça do Coronel Pacheco, No. 15, 4050-453 Porto, Portugal.
authors.forename: Ruben
authors.initials: R
authors.lastname: Fernandes
authors.affiliation: Ciências Químicas e das Biomoléculas, Escola Superior de Tecnologia de Saúde do Porto, Instituto Politécnico do Porto, Praça do Coronel Pacheco, No. 15, 4050-453 Porto, Portugal.
authors.forename: Cristina
authors.initials: C
authors.lastname: Prudêncio
authors.affiliation: Laboratório de Microbiologia, CBAA/DBEB, Instituto Superior de Agronomia, Technical University of Lisbon, Tapada da Ajuda 1349-017 Lisbon, Portugal.
authors.forename: Luísa
authors.initials: L
authors.lastname: Brito
mesh_terms: D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002611:Cheese / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008826:Microbial Sensitivity Tests; D011174:Portugal; D001618:beta-Lactamases / Q000235:genetics; D047090:beta-Lactams / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D000667:Ampicillin; D001618:beta-Lactamases