title: Absence of intervening sequences and point mutations in the V domain within 23S rRNA in Campylobacter lari isolates.
abstract: Although the absence of intervening sequences (IVSs) within the 23S rRNA genes in Campylobacter lari isolates has been described, there are apparently no reports regarding correlations between the nucleotide sequences of 23S rRNA genes and erythromycin (Ery) susceptibility in C. lari isolates. Here, we determined the minimum inhibitory concentrations of 35 C. lari isolates [n = 19 for urease-positive thermophilic Campylobacter (UPTC); n = 16 urease-negative (UN) C. lari] obtained from Asia, Europe, and North America. We found that the 18 isolates were resistant to the Ery (defined as ≧8 μg/mL), and three isolates, UPTC A1, UPTC 92251, and UPTC 504, showed increased resistance (16 μg/mL). No correlations between the IVSs in the helix 45 region within the 23S rRNA gene sequences and Ery resistance were identified in the C. lari isolates examined. In addition, no point mutations occurred at any expected or putative position within the V domain in the isolates. In conclusion, antibiotic resistance against the macrolide erythromycin is mediated through an alternative pathway to that described above.
authors.affiliation: Laboratory of Molecular Biology, School of Environmental Health Sciences, Azabu University, Sagamihara, 252-5201, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Nakajima
authors.forename: Wakana
authors.initials: W
authors.lastname: Ara
authors.forename: Shizuko
authors.initials: S
authors.lastname: Kagawa
authors.forename: John E
authors.initials: JE
authors.lastname: Moore
authors.forename: Keiko
authors.initials: K
authors.lastname: Matsubara
authors.forename: Motoo
authors.initials: M
authors.lastname: Matsuda
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001208:Asia; D001483:Base Sequence; D002169:Campylobacter Infections / Q000382:microbiology / Q000662:veterinary; D044863:Campylobacter lari / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D024881:Drug Resistance, Bacterial; D004783:Environmental Microbiology; D004917:Erythromycin / Q000494:pharmacology; D005060:Europe; D006801:Humans; D007438:Introns; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009656:North America; D017354:Point Mutation; D012338:RNA, Ribosomal, 23S / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: D000900:Anti-Bacterial Agents; D012338:RNA, Ribosomal, 23S; D004917:Erythromycin