Correlations between 23S rRNA genes and erythromycin resistance in Campylobacter jejuni

There has been no description of the prevalence of intervening sequences (IVSs) within the 23S rRNA genes in clinical Campylobacter jejuni isolated from humans, and, moreover, no studies have yet appeared describing the correlation between nucleotide sequences of 23S rRNA genes and erythromycin (Ery) resistance in human isolates. Minimum inhibitory concentration of 49 human clinical C. jejuni isolates isolated in Asia, Europe, and North America were determined, and 8 isolates were resistant to Ery (≥ 8 μg/ml; 16%). Following sequencing and alignment analyses, no correlations between the nucleotide sequences of the V domain and the IVSs within 23S rRNA gene sequences and Ery resistance occurred in the human clinical C. jejuni isolates examined. In addition, no point mutations occurred at any expected and putative positions in the V domain with the isolates. In addition, no correlations were seen between the occurrence of the IVSs and random amplified polymorphic DNA subtypes of the C. jejuni isolates. Therefore, ABC efflux pump and other resistance mechanisms(s) may be involved in the resistance to Ery in the human clinical C. jejuni isolates examined in the present study.