Abstract
The effects of ionophores on tetracycline accumulation in Escherichia coli cells were investigated in the presence of polymyxin B nonapeptide. Accumulation was inhibited by nigericin but not by valinomycin. Tetracycline accumulation was stimulated by decreasing the pH of the medium and inhibited by the addition of magnesium ions. These results indicated that tetracycline enters cells through diffusion as a protonated form (TH2) and is accumulated as a membrane-impermeable magnesium-tetracycline chelate complex (THMg+). This noncarrier diffusion hypothesis was confirmed by the fact that tetracycline accumulated in protein-free liposomes through an artificially imposed pH difference.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
