title: Emergence of Oxacillinases in Environmental Carbapenem-Resistant Acinetobacter baumannii Associated with Clinical Isolates.
abstract: Six carbapenem-resistant isolates of Acinetobacter baumannii were recovered from untreated and treated municipal wastewater of the capital city of Zagreb, Croatia. Molecular identification of environmental isolates of A. baumannii was performed by amplification, sequencing, and phylogenetic analyses of rpoB gene. The presence of blaOXAgenes encoding OXA-type carbapenemases (OXA-51-like, OXA-23, and OXA-40-like) was confirmed by multiplex PCR and sequencing. Phylogenetic analyses corroborated the affiliation of detected blaOXAgenes to three different clusters and showed association of environmental OXAs with those described from clinical isolates. This result suggests that isolates recovered from municipal wastewater are most probably of clinical origin. Furthermore, the presence of OXA-40-like (OXA-72) in an environmental A. baumannii isolate is reported for the first time. Persistence of A. baumannii harboring the clinically important OXAs in the wastewater treatment process poses a potentially significant source for horizontal gene transfer and implications for wider spread of antibiotic resistance genes.
authors.affiliation: 1 Department of Clinical Microbiology, University Hospital Centre Split , Split, Croatia .|2 University of Split School of Medicine , Split, Croatia .
authors.forename: Ivana
authors.initials: I
authors.lastname: Goic-Barisic
authors.affiliation: 3 Department of Biology, Faculty of Science, University of Zagreb , Zagreb, Croatia .
authors.forename: Jasna
authors.initials: J
authors.lastname: Hrenovic
authors.affiliation: 4 Institute of Public Health of Split and Dalmatia County , Split, Croatia .
authors.forename: Ana
authors.initials: A
authors.lastname: Kovacic
authors.affiliation: 3 Department of Biology, Faculty of Science, University of Zagreb , Zagreb, Croatia .
authors.forename: Martina Šeruga
authors.initials: MŠ
authors.lastname: Musić
mesh_terms: D040981:Acinetobacter baumannii / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D015780:Carbapenems / Q000494:pharmacology; D017523:Croatia; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D022761:Gene Transfer, Horizontal; D006801:Humans; D008826:Microbial Sensitivity Tests; D060885:Multiplex Polymerase Chain Reaction; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D062065:Wastewater / Q000382:microbiology; D014871:Water Microbiology; D018440:beta-Lactam Resistance / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D012321:DNA-Directed RNA Polymerases; D062065:Wastewater; D001618:beta-Lactamases; C108449:oxacillinase
keywords: Acinetobacter baumannii; carbapenemase; microbial drug resistance; molecular characterization; oxacillinanase; public health