Table 1. Summary on SULT forms detected in cytosolic fractions from liver and various sections of the gastrointestinal tract.
SULT levels were determined semi-quantitatively using cDNA-expressed proteins as standards. This method may involve inaccuracies in the absolute value (we estimate by a factor of up to three), but should be more accurate for comparison of the same protein in different samples (within rows). Values are means of n samples. An extended version of this Table is presented in Supplementary Table 3 (at http://www.BiochemJ.org/bj/404/bj4040207add.htm). −, below the limit of detection.
| ng SULT/mg of cytosolic protein | |||||||
|---|---|---|---|---|---|---|---|
| Rectum (n=11) | Colon (n=28) | Cecum (n=1) | Jejunum (n=1) | Ileum (n=4) | Stomach (n=1) | Liver (n=1) | |
| SULT form | |||||||
| 1A1 | 210 | 180 | 150 | 75 | 1200 | 75 | 800 |
| 1A2 | − | −* | 75 | − | −* | − | 75 |
| 1A3 | 310 | 320 | 300 | 300 | 1500 | 150 | − |
| 1B1 | 130 | 120 | 100 | 50 | 420 | 50 | 25 |
| 1C1 | − | −* | − | − | −* | 25 | − |
| 1E1 | −† | −† | 6† | 12† | 50† | −† | 100† |
| 2A1 | −† | −† | 25† | 200† | 150† | −† | 1000† |
*Some samples showed faint signals close to the limit of detection.
†Levels of SULT1E1 and 2A1 protein were paralleled by results from enzyme activity assays using characteristic substrates for these forms, oestradiol (20 nM) and DHEA (3 μM) respectively (see Supplementary Table 4 at http://www.BiochemJ.org/bj/404/bj4040207add.htm).