Prevalence of the Ribosomal RNA methylase erm(B) gene and other macrolide-resistance factors in Campylobacter isolates from different sources
Poster presented in WVA/WMA Global Conference on One Health
May 21st, 2015
Florez-Cuadrado D., Ugarte-Ruiz M., Quesada A., Palomo G., Porrero MC. and Dominguez L.
Thermophilic Campylobacter species, especially C. jejuni and C. coli, are recognized as the most common causative agents of human gastroenteritis worldwide. Even though the illness is usually self-limited, antimicrobial treatment is needed occasionally. Macrolides, such as erythromycin, are the drug of choice for campylobacteriosis treatment. Resistance to macrolides in Campylobacter is mainly related with efflux pumps and target mutations in the 23S rRNA gene (positions 2074 and 2075). Recently, the methylase gene erm(B) has been described as a new erythromycin resistance factor in Campylobacter and is located in a multidrug resistance genomic island. Eighty-eight erythromycin-resistant strains (MICs values determined by agar dilution ranged from 32 to >1024mg/L) of C. jejuni and C. coli from different sources (poultry, swine, cattle and sewage water) were selected in order to evaluate the molecular resistance mechanisms to erythromycin. Presence of erm(B) gene and target mutations in the 23S rRNA gene was tested by PCR plus sequencing. The 62.9% (56/89) of the Campylobacter strains present the mutation A2075G in the 23S rRNA gene and 1.1% (1/89) of them have the mutations A2074C and A2074G in one isolated single each. A 2.2% (2/89) of the Campylobacter isolates used in this study carry the erm(B) gene. The prevalence of the gene erm(B) in C. coli is lower than the target mutation A2075G in 23S rRNA gene but is related with high erythromycin-resistance levels. Additionally, the erm(B) gene is located in a multidrug resistance genomic island therefore this would imply a horizontal transfer of resistance to other strains of Campylobacter
 | Servicio de Zoonosis de Transmisión Alimentaria y Resistencia a Antimicrobianos (ZTA). Centro de Vigilancia Sanitaria Veterinaria (VISAVET). Universidad Complutense (UCM). |
| Departamento de Sanidad Animal. Facultad de Veterinaria. Universidad Complutense (UCM). |
 | Departamento de Bioquímica, Biología Molecular y Genética. Facultad de Veterinaria. Universidad de Extremadura (UNEX). |
Link to WVA/WMA Global Conference on One Health
