title: Isolation of tetracycline-resistant clinical Helicobacter pylori without mutations in 16S rRNA gene in Bangladesh.
abstract: The occurrence of 16S rRNA gene mutations associated with resistance to tetracycline in H. pylori isolated in Bangladesh was investigated. Tetracycline susceptibility was determined by the agar dilution method. The 16S rRNA genes of these isolates were sequenced and analyzed. A tetracycline accumulation assay was performed. DNA sequence and transformation tests of nine tetracycline-resistant (MIC = 2 microg/ml) Bangladeshi H. pylori clinical isolates showed that in no case was the resistance due to mutations in the 16S rRNA gene, the only known cause of tetracycline resistance in this pathogen. Tetracycline accumulation assays implicated altered uptake or efflux.
authors.affiliation: Laboratory Sciences Division, ICDDR,B: Centre for Health and Population Research, Dhaka, Bangladesh. dph17021@cc.okayama-u.ac.jp
authors.forename: Rasel
authors.initials: R
authors.lastname: Khan
authors.forename: Shamsun
authors.initials: S
authors.lastname: Nahar
authors.forename: Asish K
authors.initials: AK
authors.lastname: Mukhopadhyay
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Berg
authors.forename: Mian Mashhud
authors.initials: MM
authors.lastname: Ahmad
authors.forename: Keinosuke
authors.initials: K
authors.lastname: Okamoto
authors.forename: G Balakrish
authors.initials: GB
authors.lastname: Nair
authors.forename: Motiur
authors.initials: M
authors.lastname: Rahman
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001459:Bangladesh; D001483:Base Sequence; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D016481:Helicobacter Infections / Q000382:microbiology*; D016480:Helicobacter pylori / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000737:chemistry / Q000235:genetics; D013752:Tetracycline / Q000494:pharmacology*; D013753:Tetracycline Resistance; D014170:Transformation, Genetic
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D013752:Tetracycline