Glutathione transport systems of the budding yeast Saccharomyces cerevisiae.
The budding yeast Saccharomyces cerevisiae was shown to have two kinetically distinguishable glutathione transport systems. While one with high affinity (GSH-P1; KT = 0.045 mM) was regulated, the other with low affinity (GSH-P2; KT > 2 mM) was not. GSH-P1 was highly specific to glutathione, and its activity was quickly lost by suspending the cells in buffer solutions. This activity loss was not observed if glucose-containing buffer was used. In addition, rho-isolates had only about one half of the glutathione transport activity of the original (rho+) strain. Therefore, it is concluded that GSH-P1 is an ATP-driven transport system. Strong and moderate inhibition of GSH-P1 by protonophores and ionophores, respectively, are attributed to competition for ATP between GSH-P1 and proton- and cation-pumps, respectively.
Miyake
T
T
Industrial Technology Center of Okayama Prefecture, Japan.
Hazu
T
T
Yoshida
S
S
Kanayama
M
M
Tomochika
K
K
Shinoda
S
S
Ono
B
B
D000255:Adenosine Triphosphate / Q000378:metabolism; D001693:Biological Transport, Active / Q000187:drug effects; D003470:Culture Media; D003545:Cysteine / Q000378:metabolism / Q000494:pharmacology; D005978:Glutathione / Q000378:metabolism*; D007700:Kinetics; D012441:Saccharomyces cerevisiae / Q000378:metabolism*
D003470:Culture Media; D000255:Adenosine Triphosphate; D005978:Glutathione; D003545:Cysteine