Article

Antibiotic Resistance of Gram Negatives isolates from loggerhead sea turtles (Caretta caretta) in the central Mediterranean Sea

Dipartimento di Sanità Pubblica Veterinaria, Università degli Studi di Messina, Polo Universitario SS Annunziata, 98167 Messina, Italy.
Marine Pollution Bulletin (Impact Factor: 2.99). 06/2009; 58(9):1363-6. DOI: 10.1016/j.marpolbul.2009.04.020
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ABSTRACT

Previous studies on fish and marine mammals support the hypothesis that marine species harbor antibiotic resistance and therefore may serve as reservoirs for antibiotic-resistance genetic determinants. The aim of this study was to assess the resistance to antimicrobial agents of Gram negative strains isolated from loggerhead sea turtles (Carettacaretta). Oral and cloacal swabs from 19 live-stranded loggerhead sea turtles, with hooks fixed into the gut, were analyzed. The antimicrobial resistance of the isolates to 31 antibiotics was assessed using the disk-diffusion method. Conventional biochemical tests identified Citrobacter spp., Proteus spp., Enterobacter spp., Escherichia spp., Providencia spp., Morganella spp., Pantoea spp., Pseudomonas spp. and Shewanella spp. Highest prevalences of resistance was detected to carbenicillin (100%), cephalothin (92.6%), oxytetracycline (81.3%) and amoxicillin (77.8%). The isolates showing resistance to the widest range of antibiotics were identified as Citrobacterfreundii, Proteusvulgaris, Providenciarettgeri and Pseudomonasaeruginosa. In this study, antibiotic resistant bacteria reflect marine contamination by polluted effluents and C.caretta is considered a bioindicator which can be used as a monitor for pollution.

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    • "Bull. (2013), http://dx.doi.org/10.1016/j.marpolbul.2013.01.017 ples (38%) (Foti et al., 2009). In that study, however, high levels of tetracycline and amoxicillin/clavulanic acid resistance (64.9% and 48%, respectively) were described in contrast to our samples. "
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    ABSTRACT: The prevalence of antibiotic resistance and the implicated mechanisms of resistance were evaluated in Enterococcus spp. and Escherichia coli, isolated from a total of 250 faecal samples of echinoderms collected from Azorean waters (Portugal). A total of 144 enterococci (120 Enterococcus faecium, 14 E. hirae, 8 E. faecalis, 2 E. gallinarum) and 10 E. coli were recovered. High percentages of resistance in enterococci were found for erythromycin, ampicillin, tetracyclin and ciprofloxacin. The erm(A) or erm(B), tet(M) and/or tet(L), vat(D), aac(6')-aph(2″) and aph(3')-IIIa genes were found in isolates resistant to erythromycin, tetracycline, quinupristin/dalfopristin, high-level gentamicin and high-level kanamycin, respectively. Resistance in E. coli isolates was detected for streptomycin, amikacin, tetracycline and tobramycin. The aadA gene was found in streptomycin-resistant isolates and tet(A)+tet(B) genes in tetracycline-resistant isolates. The data recovered are essential to improve knowledge about the dissemination of resistant strains through marine ecosystems and the possible implications involved in transferring these resistances either to other animals or to humans.
    Full-text · Article · Feb 2013 · Marine Pollution Bulletin
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    • "They have been identified as part of the normal human gut flora and the genomes of some strains have been sequenced as part of the Human Microbiome Project [5]. Additionally, Providencia have been associated with numerous animals worldwide, including isolation from penguin feces in German zoos [6], sea turtles in the Mediterranean [7], shark mouths in Brazil [8], entomopathogenic nematodes globally [9], and snakes from Vietnam [10]. Providencia have also been found in association with insects such as blowflies [11], stable flies [12], Mexican fruit flies [13], and house flies [14]. "
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    ABSTRACT: Background Comparative genomics can be an initial step in finding the genetic basis for phenotypic differences among bacterial strains and species. Bacteria belonging to the genus Providencia have been isolated from numerous and varied environments. We sequenced, annotated and compared draft genomes of P. rettgeri, P. sneebia, P. alcalifaciens, and P. burhodogranariea. These bacterial species that were all originally isolated as infections of wild Drosophila melanogaster and have been previously shown to vary in virulence to experimentally infected flies. Results We found that these Providencia species share a large core genome, but also possess distinct sets of genes that are unique to each isolate. We compared the genomes of these isolates to draft genomes of four Providencia isolated from the human gut and found that the core genome size does not substantially change upon inclusion of the human isolates. We found many adhesion related genes among those genes that were unique to each genome. We also found that each isolate has at least one type 3 secretion system (T3SS), a known virulence factor, though not all identified T3SS belong to the same family nor are they in syntenic genomic locations. Conclusions The Providencia species examined here are characterized by high degree of genomic similarity which will likely extend to other species and isolates within this genus. The presence of T3SS islands in all of the genomes reveal that their presence is not sufficient to indicate virulence towards D. melanogaster, since some of the T3SS-bearing isolates are known to cause little mortality. The variation in adhesion genes and the presence of T3SSs indicates that host cell adhesion is likely an important aspect of Providencia virulence.
    Full-text · Article · Nov 2012 · BMC Genomics
    • "Sea turtles have been used as bio-indicators for pollution in the coastal marine habitats. For example, antibiotic-resistant bacteria isolated from green turtles and loggerheads are causing deep concern regarding the dissemination of resistance to antibiotics in marine wildlife (Al-Bahry et al., 2009a,b, 2011; Foti et al., 2009). Antibiotic-resistant bacteria have been found in the egg-shells and egg contents of the green turtle, Chelonia mydas (Al-Bahry et al., 2009a). "
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    No preview · Article · Mar 2012 · Chemosphere
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