Tags

Type your tag names separated by a space and hit enter

Molecular characterization of resistance to extended-spectrum cephalosporins in clinical Escherichia coli isolates from companion animals in the United States.
Antimicrob Agents Chemother. 2011 Dec; 55(12):5666-75.AA

Abstract

Resistance to extended-spectrum cephalosporins (ESC) among members of the family Enterobacteriaceae occurs worldwide; however, little is known about ESC resistance in Escherichia coli strains from companion animals. Clinical isolates of E. coli were collected from veterinary diagnostic laboratories throughout the United States from 2008 to 2009. E. coli isolates (n = 54) with reduced susceptibility to ceftazidime or cefotaxime (MIC ≥ 16 μg/ml) and extended-spectrum-β-lactamase (ESBL) phenotypes were analyzed. PCR and sequencing were used to detect mutations in ESBL-encoding genes and the regulatory region of the chromosomal gene ampC. Conjugation experiments and plasmid identification were conducted to examine the transferability of resistance to ESCs. All isolates carried the bla(CTX-M-1)-group β-lactamase genes in addition to one or more of the following β-lactamase genes: bla(TEM), bla(SHV-3), bla(CMY-2), bla(CTX-M-14-like), and bla(OXA-1.) Different bla(TEM) sequence variants were detected in some isolates (n = 40). Three isolates harbored a bla(TEM-181) gene with a novel mutation resulting in an Ala184Val substitution. Approximately 78% of the isolates had mutations in promoter/attenuator regions of the chromosomal gene ampC, one of which was a novel insertion of adenine between bases -28 and -29. Plasmids ranging in size from 11 to 233 kbp were detected in the isolates, with a common plasmid size of 93 kbp identified in 60% of isolates. Plasmid-mediated transfer of β-lactamase genes increased the MICs (≥ 16-fold) of ESCs for transconjugants. Replicon typing among isolates revealed the predominance of IncI and IncFIA plasmids, followed by IncFIB plasmids. This study shows the emergence of conjugative plasmid-borne ESBLs among E. coli strains from companion animals in the United States, which may compromise the effective therapeutic use of ESCs in veterinary medicine.

Authors+Show Affiliations

Division of Microbiology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas 72079, USA. bashar.shaheen@fda.hhs.govNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

21947397

Citation

Shaheen, Bashar W., et al. "Molecular Characterization of Resistance to Extended-spectrum Cephalosporins in Clinical Escherichia Coli Isolates From Companion Animals in the United States." Antimicrobial Agents and Chemotherapy, vol. 55, no. 12, 2011, pp. 5666-75.
Shaheen BW, Nayak R, Foley SL, et al. Molecular characterization of resistance to extended-spectrum cephalosporins in clinical Escherichia coli isolates from companion animals in the United States. Antimicrob Agents Chemother. 2011;55(12):5666-75.
Shaheen, B. W., Nayak, R., Foley, S. L., Kweon, O., Deck, J., Park, M., Rafii, F., & Boothe, D. M. (2011). Molecular characterization of resistance to extended-spectrum cephalosporins in clinical Escherichia coli isolates from companion animals in the United States. Antimicrobial Agents and Chemotherapy, 55(12), 5666-75. https://doi.org/10.1128/AAC.00656-11
Shaheen BW, et al. Molecular Characterization of Resistance to Extended-spectrum Cephalosporins in Clinical Escherichia Coli Isolates From Companion Animals in the United States. Antimicrob Agents Chemother. 2011;55(12):5666-75. PubMed PMID: 21947397.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Molecular characterization of resistance to extended-spectrum cephalosporins in clinical Escherichia coli isolates from companion animals in the United States. AU - Shaheen,Bashar W, AU - Nayak,Rajesh, AU - Foley,Steven L, AU - Kweon,Ohgew, AU - Deck,Joanna, AU - Park,Miseon, AU - Rafii,Fatemeh, AU - Boothe,Dawn M, Y1 - 2011/09/26/ PY - 2011/9/28/entrez PY - 2011/9/29/pubmed PY - 2012/3/30/medline SP - 5666 EP - 75 JF - Antimicrobial agents and chemotherapy JO - Antimicrob Agents Chemother VL - 55 IS - 12 N2 - Resistance to extended-spectrum cephalosporins (ESC) among members of the family Enterobacteriaceae occurs worldwide; however, little is known about ESC resistance in Escherichia coli strains from companion animals. Clinical isolates of E. coli were collected from veterinary diagnostic laboratories throughout the United States from 2008 to 2009. E. coli isolates (n = 54) with reduced susceptibility to ceftazidime or cefotaxime (MIC ≥ 16 μg/ml) and extended-spectrum-β-lactamase (ESBL) phenotypes were analyzed. PCR and sequencing were used to detect mutations in ESBL-encoding genes and the regulatory region of the chromosomal gene ampC. Conjugation experiments and plasmid identification were conducted to examine the transferability of resistance to ESCs. All isolates carried the bla(CTX-M-1)-group β-lactamase genes in addition to one or more of the following β-lactamase genes: bla(TEM), bla(SHV-3), bla(CMY-2), bla(CTX-M-14-like), and bla(OXA-1.) Different bla(TEM) sequence variants were detected in some isolates (n = 40). Three isolates harbored a bla(TEM-181) gene with a novel mutation resulting in an Ala184Val substitution. Approximately 78% of the isolates had mutations in promoter/attenuator regions of the chromosomal gene ampC, one of which was a novel insertion of adenine between bases -28 and -29. Plasmids ranging in size from 11 to 233 kbp were detected in the isolates, with a common plasmid size of 93 kbp identified in 60% of isolates. Plasmid-mediated transfer of β-lactamase genes increased the MICs (≥ 16-fold) of ESCs for transconjugants. Replicon typing among isolates revealed the predominance of IncI and IncFIA plasmids, followed by IncFIB plasmids. This study shows the emergence of conjugative plasmid-borne ESBLs among E. coli strains from companion animals in the United States, which may compromise the effective therapeutic use of ESCs in veterinary medicine. SN - 1098-6596 UR - https://www.unboundmedicine.com/medline/citation/21947397/Molecular_characterization_of_resistance_to_extended_spectrum_cephalosporins_in_clinical_Escherichia_coli_isolates_from_companion_animals_in_the_United_States_ L2 - https://journals.asm.org/doi/10.1128/AAC.00656-11?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub=pubmed DB - PRIME DP - Unbound Medicine ER -