Uptake of minocycline and tetracycline by tetracycline-susceptible and -resistant bacteria.
Minocycline (7-dimethylamino-6-demethyl-6-deoxytetracycline) is a new semisynthetic tetracycline with potent activity against tetracycline-susceptible bacterial pathogens and unique activity against tetracycline-resistant staphylococci. Studies to determine the basis for this unique activity showed that, whereas tetracycline-resistant staphylococci took up less (3)H-tetracycline than the susceptible cells, both the tetracycline-resistant and -susceptible cells accumulated equivalent amounts of (14)C-minocycline. In contrast, tetracycline-resistant Escherichia coli cells were relatively resistant to minocycline and accumulated less of both drugs than did the susceptible organisms. It is proposed that minocycline is effective against tetracycline-resistant staphylococci because of its ability to penetrate the cells sufficiently to reach inhibiting concentrations at sensitive reaction sites.
D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000187:drug effects* / Q000378:metabolism; D008911:Minocycline / Q000378:metabolism; D013210:Staphylococcus / Q000187:drug effects* / Q000378:metabolism; D013752:Tetracycline / Q000378:metabolism*
D013752:Tetracycline; D008911:Minocycline