Dataset Information

The Current State of Macrolide Resistance in Campylobacter spp.: Trends and Impacts of Resistance Mechanisms.

ABSTRACT: Campylobacter spp., especially Campylobacter jejuni and C. coli, are leading bacterial foodborne pathogens worldwide. In the United States, an estimated 0.8 million cases of campylobacteriosis occur annually, mostly involving C. jejuni Campylobacteriosis is generally self-limiting, but in severe cases, treatment with antibiotics may be mandated. The increasing incidence of fluoroquinolone resistance in Campylobacter has rendered macrolides such as erythromycin and azithromycin the drugs of choice for human campylobacteriosis. The prevalence of macrolide resistance in C. jejuni remains low, but macrolide resistance can be common in C. coli Substitutions in the 23S rRNA gene, specifically A2075G, and less frequently A2074C/G, remain the most common mechanism for high-level resistance to macrolides. In C. jejuni, resistance mediated by such substitutions is accompanied by a reduced ability to colonize chickens and other fitness costs, potentially contributing to the low incidence of macrolide resistance. Interestingly, similar fitness impacts have not been noted in C. coli Also noteworthy is a novel mechanism first reported in 2014 for a C. coli isolate from China and mediated by erm(B) harbored on multidrug resistance genomic islands. The incidence of erm(B) appears to reflect clonal expansion of certain strains, and whole-genome sequencing has been critical to the elucidation of erm(B)-associated macrolide resistance in Campylobacter spp. With the exception of one report from Spain, erm(B)-mediated macrolide resistance has been restricted to Campylobacter spp., mostly C. coli, of animal and human origin from China. If erm(B)-mediated macrolide resistance does not confer fitness costs in C. jejuni, the range of this gene may expand in C. jejuni, threatening to compromise treatment effectiveness for severe campylobacteriosis cases.

SUBMITTER: Bolinger H

PROVIDER: S-EPMC5452823 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The Current State of Macrolide Resistance in Campylobacter spp.: Trends and Impacts of Resistance Mechanisms.

Bolinger Hannah H Kathariou Sophia S

Applied and environmental microbiology 20170531 12

Campylobacter spp., especially Campylobacter jejuni and C. coli, are leading bacterial foodborne pathogens worldwide. In the United States, an estimated 0.8 million cases of campylobacteriosis occur annually, mostly involving C. jejuni Campylobacteriosis is generally self-limiting, but in severe cases, treatment with antibiotics may be mandated. The increasing incidence of fluoroquinolone resistance in Campylobacter has rendered macrolides such as erythromycin ...[more]

PMID: 28411226

Similar Datasets

Project description:A collection of 23 macrolide-resistant Campylobacter isolates from different geographic areas was investigated to determine the mechanism and stability of macrolide resistance. The isolates were identified as Campylobacter jejuni or Campylobacter coli based on the results of the hippurate biochemical test in addition to five PCR-based genotypic methods. Three point mutations at two positions within the peptidyl transferase region in domain V of the 23S rRNA gene were identified. About 78% of the resistant isolates exhibited an A-->G transition at Escherichia coli equivalent base 2059 of the 23S rRNA gene. The isolates possessing this mutation showed a wide range of erythromycin and clarithromycin MICs. Thus, this mutation may incur a greater probability of treatment failure in populations infected by resistant Campylobacter isolates. Another macrolide-associated mutation (A-->C transversion), at E. coli equivalent base 2058, was detected in about 13% of the isolates. An A-->G transition at a position cognate with E. coli 23S rRNA base 2058, which is homologous to the A2142G mutation commonly described in Helicobacter pylori, was also identified in one of the C. jejuni isolates examined. In the majority of C. jejuni isolates, the mutations in the 23S rRNA gene were homozygous except in two cases where the mutation was found in two of the three copies of the target gene. Natural transformation demonstrated the transfer of the macrolide resistance phenotype from a resistant Campylobacter isolate to a susceptible Campylobacter isolate. Growth rates of the resulting transformants containing A-2058-->C or A-2059-->G mutations were similar to that of the parental isolate. The erythromycin resistance of six of seven representative isolates was found to be stable after successive subculturing in the absence of erythromycin selection pressure regardless of the resistance level, the position of the mutation, or the number of the mutated copies of the target gene. One C. jejuni isolate showing an A-2058-->G mutation, however, reverted to erythromycin and clarithromycin susceptibility after 55 subcultures on erythromycin-free medium. Investigation of ribosomal proteins L4 and L22 by sequence analysis in five representative isolates of C. jejuni and C. coli demonstrated no significant macrolide resistance-associated alterations in either the L4 or the L22 protein that might explain either macrolide resistance or enhancement of the resistance level.

Dataset Information

The Current State of Macrolide Resistance in Campylobacter spp.: Trends and Impacts of Resistance Mechanisms.

Publications

The Current State of Macrolide Resistance in Campylobacter spp.: Trends and Impacts of Resistance Mechanisms.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets