Open AccessDoxorubicin‐efflux pump in Haloferax voleanii is energized by ATP
Author(s) -
Komatsubara Masaki,
Abe Akihito,
Okumura Ryo,
Miyauchi Seiji,
Kamo Naoki
Publication year - 1996
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1996.tb08183.x
Subject(s) - efflux , haloferax volcanii , atp binding cassette transporter , chemistry , chemiosmosis , membrane potential , biophysics , transporter , biochemistry , biology , atp synthase , enzyme , archaea , gene
Haloferax voleanii acquires resistance to doxorubicin, and this acquisition involves an active extrusion of lipophilic drugs. We have investigated what this drug‐efflux transporter utilizes as an energy source to expel drugs from the cells. The efflux activity was estimated from the direct measurement of drug efflux rate and from the steady‐state level of drug accumulation. Cells treated with N , N ′‐dicyclohexyl‐carbodiimide showed a significant decrease in the efflux activity without changing membrane potential and Na + ‐electrochemical potential. This efflux system is energized by ATP but not by either a H + ‐ or Na + ‐electrochemical potential difference.