Emergence of Multidrug-Resistant Campylobacter Species Isolates with a Horizontally Acquired rRNA Methylase

Abstract

Antibiotic-resistant Campylobacter constitutes a serious threat to public health, and resistance to macrolides is of particular concern, as this class of antibiotics is the drug of choice for clinical therapy of campylobacteriosis. Very recently, a horizontally transferrable macrolide resistance mediated by the rRNA methylase gene erm(B) was reported in a Campylobacter coli isolate, but little is known about the dissemination of erm(B) among Campylobacter isolates and the association of erm(B)-carrying isolates with clinical disease. To address this question and facilitate the control of antibiotic-resistant Campylobacter, we determined the distribution of erm(B) in 1,554 C. coli and Campylobacter jejuni isolates derived from food-producing animals and clinically confirmed human diarrheal cases. The results revealed that 58 of the examined isolates harbored erm(B) and exhibited high-level resistance to macrolides, and most were recent isolates, derived in 2011-2012. In addition, the erm(B)-positive isolates were all resistant to fluoroquinolones, another clinically important antibiotic used for treating campylobacteriosis. The erm(B) gene is found to be associated with chromosomal multidrug resistance genomic islands (MDRGIs) of Gram-positive origin or with plasmids of various sizes. All MDRGIs were transferrable to macrolide-susceptible C. jejuni by natural transformation under laboratory conditions. Molecular typing of the erm(B)-carrying isolates by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) identified diverse genotypes and outbreak-associated diarrheal isolates. Molecular typing also suggested zoonotic transmission of erm(B)-positive Campylobacter. These findings reveal an emerging and alarming trend of dissemination of erm(B) and MDRGIs in Campylobacter and underscore the need for heightened efforts to control their further spread.

High Prevalence and Predominance of the aph(2″)-If Gene Conferring Aminoglycoside Resistance in Campylobacter

“…These results indicate that the aph(2Љ)-If-containing segment is inserted in a conserved location on the chromosome and is widely spread in the gentamicin-resistant Campylobacter isolates in China. (14), and the genomic islands harboring aminoglycoside resistance and multidrug resistance were identified between cadF and CCO1582 on the chromosome in C. coli (16,22). In the present study, multiple aminoglycoside resistance genes and a cat gene are found to be located in a novel spot between Cj0299 and panB, which has never been reported previously.…”

Constitutive and Inducible Expression of the rRNA Methylase Gene erm (B) in Campylobacter

“…Macrolide resistance among Campylobacter jejuni and Campylobacter coli strains is generally much more severe in developing countries than in developed countries (5)(6)(7)(8)(9). In addition, there is a much higher frequency of macrolide resistance in C. coli than that in C. jejuni, both in isolates derived from humans and in those from food animals (6,10,11).…”

“…In addition, there is a much higher frequency of macrolide resistance in C. coli than that in C. jejuni, both in isolates derived from humans and in those from food animals (6, 10, 11). Very recently, the rRNA methylase Erm(B) has emerged as an important mechanism of acquired macrolide-lincosamide (ML) resistance in C. jejuni and C. coli (8,12,13), the two most common human disease-causing Campylobacter species. In Gram-positive bacteria, the expression of erm genes can be either constitutive or inducible (14).…”

“…Details of the origins and identification of the above-mentioned 27 Campylobacter strains have been described previously (8).…”

Influência da vida séssil e planctônica no perfil de resistência antimicrobiana de Campylobacter jejuni isoladas de carcaças de frangos comercializadas no Brasil

“…A resistência de alto nível a eritromicina pode estar relacionada à presença do gene erm, o qual pode estar associado com ilhas de resistência multidrogas cromossômicas ou de plasmídeos transferíveis (WANG et al, 2015;EFSA, 2017 Os mecanismos atribuídos à resistência à tetraciclina estão relacionados ao efluxo, por meio da diminuição da acumulação da droga no interior da célula;…”