TY - JOUR

T1 - Characterization of oxytetracycline-resistant heterotrophic bacteria originating from hospital and freshwater fishfarm environments England and Ireland

AU - Huys, Geert

AU - Rhodes, Geert

AU - McGann, Patrick

AU - Denys, Rik

AU - Pickup, Roger

AU - Hiney, Maura

AU - Smith, Peter

AU - Swings, Jean

PY - 2000/12/31

Y1 - 2000/12/31

N2 - This ecotaxonomic study compared the antibiotic tolerance among culturable oxytetracyline-resistant (Otr) heterotrophic strains isolated from two aquatic environments representing human activities in health care and aquaculture, namely hospital effluents and freshwater fishfarms. Using a standardized methodology, samples taken in England and Ireland were analyzed to determine the antibiotic tolerance profiles of two groups of culturable Otr bacterial isolates at the intergeneric and intrageneric level comprising heterotrophs (189 strains) and mesophilic Aeromonas spp. (153 strains), respectively. Antibiogram data of heterotrophic isolates revealed that Irish hospital strains comprised higher frequencies of multi-tolerance than those originating from fishfarm environments whereas a reverse correlation was found among the English heterotrophs. Polyphasic identification of the isolates using fatty acid analysis and API 20E profiling showed that this difference arose from the unique taxonomic diversity within each heterotrophic strain set. Acinetobacter (27%) and Brevundimonas (22%) were predominant among the Irish Otr fishfarm isolates, whereas isolates originating from the English aquaculture site almost entirely consisted of Stenotrophomonas rnaltophilia (86%) exhibiting high frequencies of tolerance to ampicillin and streptomycin. Within both the English and the Irish Otr Aeromonas strain sets, on the other hand, the hospital strain sets displayed higher numbers of multi-tolerant isolates than to fishfarm isolates although country-specific differences were observed for individual antimicrobial agents. The typical occurrence of kanamycin-tolerant aeromonads in the Irish hospital site could to some extent be linked to the typical presence of A. hydrophila DNA hybridization group (HG) 3 strains as determined by fatty acid analysis and fluorescent amplified fragment length polymorphism (FAFLP) fingerprinting. Essentially, these data indicate that tolerance profiles in a specific environment of one country do not necessarily reflect the corresponding tolerance profiles of the same type of environment in another country, and this mainly as a result of the unique taxonomic composition of each site. Otr representatives of Acinetobacter, S. maltophilia, and A. veronii biovar sobria HG8 were common to most if not all of the four sites under study, indicating that these three taxa may serve as potential indicator organisms for monitoring antibiotic tolerance among indigenous bacterial populations in various aquatic environments.

AB - This ecotaxonomic study compared the antibiotic tolerance among culturable oxytetracyline-resistant (Otr) heterotrophic strains isolated from two aquatic environments representing human activities in health care and aquaculture, namely hospital effluents and freshwater fishfarms. Using a standardized methodology, samples taken in England and Ireland were analyzed to determine the antibiotic tolerance profiles of two groups of culturable Otr bacterial isolates at the intergeneric and intrageneric level comprising heterotrophs (189 strains) and mesophilic Aeromonas spp. (153 strains), respectively. Antibiogram data of heterotrophic isolates revealed that Irish hospital strains comprised higher frequencies of multi-tolerance than those originating from fishfarm environments whereas a reverse correlation was found among the English heterotrophs. Polyphasic identification of the isolates using fatty acid analysis and API 20E profiling showed that this difference arose from the unique taxonomic diversity within each heterotrophic strain set. Acinetobacter (27%) and Brevundimonas (22%) were predominant among the Irish Otr fishfarm isolates, whereas isolates originating from the English aquaculture site almost entirely consisted of Stenotrophomonas rnaltophilia (86%) exhibiting high frequencies of tolerance to ampicillin and streptomycin. Within both the English and the Irish Otr Aeromonas strain sets, on the other hand, the hospital strain sets displayed higher numbers of multi-tolerant isolates than to fishfarm isolates although country-specific differences were observed for individual antimicrobial agents. The typical occurrence of kanamycin-tolerant aeromonads in the Irish hospital site could to some extent be linked to the typical presence of A. hydrophila DNA hybridization group (HG) 3 strains as determined by fatty acid analysis and fluorescent amplified fragment length polymorphism (FAFLP) fingerprinting. Essentially, these data indicate that tolerance profiles in a specific environment of one country do not necessarily reflect the corresponding tolerance profiles of the same type of environment in another country, and this mainly as a result of the unique taxonomic composition of each site. Otr representatives of Acinetobacter, S. maltophilia, and A. veronii biovar sobria HG8 were common to most if not all of the four sites under study, indicating that these three taxa may serve as potential indicator organisms for monitoring antibiotic tolerance among indigenous bacterial populations in various aquatic environments.

KW - Aeromonas

KW - Antibiotic tolerance

KW - FAFLP

KW - Fatty acid analysis

KW - Freshwater fishfarms

KW - Hospital effluent

KW - Oxytetracycline

U2 - 10.1016/S0723-2020(00)80036-3

DO - 10.1016/S0723-2020(00)80036-3

M3 - Journal article

C2 - 11249032

AN - SCOPUS:0034486130

VL - 23

SP - 599

EP - 606

JO - Systematic and Applied Microbiology

JF - Systematic and Applied Microbiology

SN - 0723-2020

IS - 4

ER -