Time-kill study of the activity of telithromycin against macrolide-resistant Streptococcus pneumoniae Isolates with 23S rRNA mutations and changes in ribosomal proteins L4 and L22.
نویسندگان
چکیده
By use of a time-kill methodology, the antipneumococcal activity of telithromycin was determined against macrolide-resistant S. pneumoniae isolates having mutations in the 23S rRNA gene and changes in the ribosomal proteins L4 and L22. Telithromycin had MICs ranging between 0.03 and 0.25 microg/ml and was bactericidal against four of seven strains after 24 h at two times the MIC.
منابع مشابه
Mechanisms of resistance to telithromycin in Streptococcus pneumoniae.
Reports of ketolide resistance remain scarce, however, a few laboratory-derived and clinical isolates of resistant Streptococcus pneumoniae have been documented. Mutations in key telithromycin-binding sites such as domains II and V of the 23S rRNA and ribosomal proteins L4 and L22, as well as mutations of the resistance determinant erm(B) are associated with elevated telithromycin MICs. Mutatio...
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 49 7 شماره
صفحات -
تاریخ انتشار 2005