7A and lane 6 in Fig. 7B), as described above. These may be partially due to occurrence of IVS within the 16S rRNA genes from these isolates and fragmentation of the primary 16S rRNA transcripts among these isolates. However, we have not clarified the nature of the 16S rRNA genes from these isolates, yet. Therefore, sequencing and alignment analyses of the complete 16S rRNA genes from these isolates are needed to identify the nature of the rRNA from these two Campylobacter species. Research to examine this is now in progress. Conclusions
Consequently, in 267 isolates of 269 Campylobacter isolates of the nine species (n = 56 C. jejuni; n = 11 C. coli; n = 33 C. fetus: n = 65 C. lari; n = 43 C. upsaliensis;
n = 30 C. hyointestinalis; Selleckchem PARP inhibitor n = 14 C. sputorum; n = 10 C. concisus; n = 7 C. curvus) examined, the absence of IVSs was identified in helix 25 region within 23S rRNA genes. Thus, IVS is extremely rare in the helix 25 region within the 23S rRNA genes from the Campylobacter organisms. The occurrence of IVSs with the two typical Campylobacter species, were shown in helix 45 region at a high percentage (54% for C. jejeuni n = 56; 45% for C. coli n = 11). We also identified the majority PS-341 concentration (62/83) of isolates from the three Campylobacter species of C. fetus, C. upsaliensis and C. curvus to carry IVSs in helix 45. However, in a total of 54 isolates of the three species of C. hyointestinalis (n = 30), C. sputorum (n = 14) and C. concisus (n = 10), no IVSs were identified in the region. Thus, Ribonucleotide reductase in conclusion,
no IVSs were identified in 105 isolates of three Campylobacter species (C. hyointestinalis, C. concisus and C. lari) both in the 25 and 45 helix regions. In addition, intact 23S rRNAs were identified in the purified RNA fractions in Campylobacter isolates containing no IVSs, and no 23S rRNA and fragmented other smaller RNA fragments were evident in the isolates containing IVSs. Methods Campylobacter isolates and genomic DNA preparation A total of 204 Campylobacter isolates [C. jejuni (n = 56); C. coli (n = 11); C. fetus (n = 33) C. upsaliensis (n = 43); C. hyointestinalis (n = 30); C. sputorum biovar sputorum (n = 4); biovar fecalis (n = 5); biovar paraureolyticus (n = 5); C. concisus (n = 10); C. curvus (n = 7)] were used in the present study (Table 2). Genomic DNA was prepared from Campylobacter cells by cethyltrimethyl ammonium bromide and proteinase K treatments, phenol-chloroform extraction and ethanol precipitation . PCR amplification, cloning and sequencing We have already designed two PCR primer pairs, f-/r-Cl23h25, constructed to amplify helix 25 region and f-/r-Cl23h45, helix 45 region within the 23S rRNA gene sequences, based on the 23S rRNA gene sequence information from 12 UPTC isolates (DDBJ/EMBL/GenBank accsssion numbers, AB287301-AB287312), C. jejuni TGH9011 (Z29326) and C. coli VC167 (U09611) (Fig. 8) .