Title: Ribosomal operon intergenic sequence (IGS) heterogeneity in Campylobacter coli and Campylobacter jejuni Authors
|Ladely, Scott - USDA-FSIS|
Submitted to: American Society for Microbiology
Publication Type: Abstract Only
Publication Acceptance Date: May 17, 2009
Publication Date: May 19, 2009
Citation: Meinersmann, R.J., Ladely, S.R. 2009. Ribosomal operon intergenic sequence (IGS) heterogeneity in Campylobacter coli and Campylobacter jejuni. American Society for Microbiology. May 17- 21, 2009. Philadelphia, PA. R-0027/758. Technical Abstract: Campylobacter jejuni and Campylobacter coli are closely related species that can not be distinguished by their 16S or 23S rRNA genes. However, the intergenic sequence (IGS) fragment that is between the 16S and 23S genes is markedly different and characteristic for each species. A peculiarity of the genomic sequence for C. coli RM2228 (Genbank # AAFL01000000) is that two of the rRNA operons have an IGS that is characteristic of C. coli and the third operon is characteristic of C. jejuni. Primers for PCR were designed such that the characteristic C. coli product would be 327 base-pairs (bp) and the C. jejuni product would be 166 bp. A strain with the heterogeneity like that in C. coli RM2228 should yield products of both sizes. To determine the extent of the congruence of the IGS with the C. jejuni/coli species, DNA from a panel of randomly collected C. coli (n=132) and C. jejuni (n=95) isolates were tested by PCR with the primers. All of the isolates yielded products of the predicted size for the species and none yielded fragments of both predicted sizes. To verify the Genbank data for C. coli RM2228, each ribosomal operon from the isolate was individually amplified by PCR and tested with the IGS primer pair. Products of both sizes were produced from the correct operon as predicted from the genomic data. Thus, the cross species heterogeneity of the IGS seen in C. coli RM2228 is infrequent and that strain is extraordinary for its ribosomal operon structure.