Glutathione content and redox state of cytosolic rxYFP in various yeast strains
. | . | . | Glutathione content (pmol/106 cells)b . | . | . | . | . | |
|---|---|---|---|---|---|---|---|---|
| Strain . | Relevant genotype . | Suppl.a . | GSH . | GSSG . | GSSG/GSH . | Oxidized rxYFPc . | E′cytosold . | |
| % | % | |||||||
| M4745 | wild type | 206 ± 4 | 9.2 ± 0.4 | 4 | 10 ± 1 | −289 mV | ||
| M4860 | glr1 | 172 ± 3 | 33 ± 3 | 19 | 56 ± 3 | −252 mV | ||
| M4860 | glr1 | GSSG | 265 ± 9 | 302 ± 5 | 114 | 84 ± 1 | ND | |
| M4859 | glr1 met15 | GSH | 267 ± 6 | 161 ± 3 | 60 | 75 ± 2 | ND | |
| M4859 | glr1 met15 | GSSG | 186 ± 6 | 417 ± 9 | 225 | 92 ± 1 | ≥ −227 mV | |
| M5059 | glrl grx1 grx2 | 225 ± 3 | 67 ± 1 | 30 | ND | −245 mV | ||
. | . | . | Glutathione content (pmol/106 cells)b . | . | . | . | . | |
|---|---|---|---|---|---|---|---|---|
| Strain . | Relevant genotype . | Suppl.a . | GSH . | GSSG . | GSSG/GSH . | Oxidized rxYFPc . | E′cytosold . | |
| % | % | |||||||
| M4745 | wild type | 206 ± 4 | 9.2 ± 0.4 | 4 | 10 ± 1 | −289 mV | ||
| M4860 | glr1 | 172 ± 3 | 33 ± 3 | 19 | 56 ± 3 | −252 mV | ||
| M4860 | glr1 | GSSG | 265 ± 9 | 302 ± 5 | 114 | 84 ± 1 | ND | |
| M4859 | glr1 met15 | GSH | 267 ± 6 | 161 ± 3 | 60 | 75 ± 2 | ND | |
| M4859 | glr1 met15 | GSSG | 186 ± 6 | 417 ± 9 | 225 | 92 ± 1 | ≥ −227 mV | |
| M5059 | glrl grx1 grx2 | 225 ± 3 | 67 ± 1 | 30 | ND | −245 mV | ||
Strains were grown in SC medium at 30°C. GSH and GSSG indicate supplementation of SC-Met medium with either 1 mM GSH or GSSG.
In order to calculate the amount of GSH or GSSG per 106 cells, one OD600 U was determined for M4745 to be 1.5·107 cells/ml. Values are given as the mean ± SD of measurements on three independent cultures.
The proportion of oxidized cytosolic rxYFP (mean ± SD; n = 3) was determined by spectrofluorometric redox titration as described in Materials and methods.
Cytosolic redox potentials (E′cytosol) were calculated from the pulse-chase end point redox distributions given in Figs. 2 and 3 and an E°′ of −265 mV for rxYFP (Table II).