Antibiotic susceptibility profiles and first report of TEM extended-spectrum β-lactamase in Pseudomonas fluorescens from coastal waters of the Kaštela Bay, Croatia.
The aim of this study was to investigate the antibiotic susceptibility profiles and the presence of extended-spectrum-β-lactamases (ESBLs) in Pseudomonas fluorescens isolates from coastal waters of the Kaštela Bay, Croatia. Twenty-two water samples were collected during 2009. Isolates were tested for susceptibilities to 13 antibiotics by Etest. ESBL production was confirmed by double-disk synergy test carried out on Mueller-Hinton agar plates containing efflux pump inhibitor Phe-Arg-β-naphthylamide dihydrochloride. PCR and DNA sequencing analysis were used to identify ESBL-encoding genes. The transferability of cephalosporin resistance was tested by conjugation experiments. Genetic relatedness of ESBL-producing isolates was determined by random amplified polymorphic DNA (RAPD) analysis. Out of 185 P. fluorescens isolates recovered, 70 (37.8%) demonstrated multiresistance phenotype with highest rates of resistance to tetracycline (61.6%), aztreonam (31.9%), meropenem (17.3%), ceftazidime (15.1%) and cefotaxime (12.4%). Ten (5.4%) isolates were identified as ESBL producers. All isolates carried chromosomally located bla (TEM-116) gene. RAPD analysis identified four different genotypes. Here, we demonstrated a baseline profiles of antimicrobial resistance of P. fluorescens from coastal waters of the Kaštela Bay, Croatia. To our knowledge, this is the first report of the presence of TEM-type ESBL in P. fluorescens, indicating this bacterium as a reservoir of antibiotic resistance genes with clinical relevance.
Department of Biology, Faculty of Science, University of Split, N. Tesle 12, 21000 Split, Croatia. ana.maravic@pmfst.hr
Ana
A
Maravić
Mirjana
M
Skočibušić
Ivica
I
Samanić
Jasna
J
Puizina
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016000:Cluster Analysis; D003227:Conjugation, Genetic; D017523:Croatia; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D022761:Gene Transfer, Horizontal; D005838:Genotype; D008826:Microbial Sensitivity Tests; D058889:Molecular Typing; D016133:Polymerase Chain Reaction; D011551:Pseudomonas fluorescens / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D019105:Random Amplified Polymorphic DNA Technique; D012623:Seawater / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D001618:beta-Lactamases