竹中　祐子
   Department   School of Medicine(Tokyo Women's Medical University Hospital), School of Medicine
   Position   Assistant Professor
Article types Original article
Language English
Peer review Peer reviewed
Title Propionibacterium acnes is developing gradual increase in resistance to oral tetracyclines.
Journal Formal name：Journal of medical microbiology
Abbreviation：J Med Microbiol
ISSN code：(1473-5644)0022-2615(Linking)
Domestic / ForeginForegin
Volume, Issue, Page 66(1),pp.8-12
Author and coauthor Nakase Keisuke, Nakaminami Hidemasa, Takenaka Yuko, Hayashi Nobukazu, Kawashima Makoto, Noguchi Norihisa
Publication date 2017/01
Summary Propionibacterium acnes is an anaerobic bacterium that causes deep infection in organs and prosthetic joints, in addition to acne vulgaris. Many tetracycline-resistant P. acnes strains have been isolated because oral tetracyclines are frequently used as an acne treatment against P. acnes. In this study, we found a novel tetracycline resistance mechanism in P. acnes. Three doxycycline-resistant (MIC: 16 µg ml-1) strains were isolated from 69 strains in acne patients in Japan between 2010 and 2011. Additionally, six insusceptible strains (MIC: 1-2 µg ml-1) that had reduced susceptibility compared to susceptible strains (MIC: ≤0.5 µg ml-1) were identified. All doxycycline-resistant strains had a G1036C mutation in the 16S rRNA gene in addition to an amino acid substitution in the ribosomal S10 protein encoded by rpsJ. By contrast, insusceptible strains had an amino acid substitution in the S10 protein but no mutation in the 16S rRNA. When the mutant with decreased susceptibility to doxycycline was obtained in vitro, only the mutated S10 protein was found (MIC: 4 µg ml-1), not the mutated 16S rRNA gene. This result shows that the S10 protein amino acid substitution contributes to reduced doxycycline susceptibility in P. acnes and suggests that tetracycline resistance is acquired through a 16S rRNA mutation after the S10 protein amino acid substitution causes reduced susceptibility.
DOI 10.1099/jmm.0.000392
PMID 28218057