Time min | 13-cRA as Substrate | 9-cRA as Substrate | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
13-cRA | 9-cRA | t-RA | 13-cRA | 9-cRA | t-RA | |||||||
ng2-a | %2-b | ng | % | ng | % | ng | % | ng | % | ng | % | |
0 | 50 ± 3 | 100 | ND2-c | 0 | ND | 0 | ND | 0 | 50 ± 4 | 100 | ND | 0 |
5 | 41 ± 1 | 89 | ND | 0 | 5 ± 0.3 | 11 | ND | 0 | 43 ± 2 | 92 | 4 ± 1 | 8 |
15 | 27 ± 2 | 68 | 1 ± 0.2 | 2 | 12 ± 1 | 30 | 2 ± 0.5 | 4 | 38 ± 5 | 81 | 7 ± 1 | 15 |
30 | 23 ± 1 | 58 | 1 ± 0.3 | 2 | 16 ± 2 | 40 | 2 ± 0.3 | 5 | 31 ± 1 | 65 | 14 ± 1 | 30 |
60 | 11 ± 2 | 31 | 2 ± 0.4 | 6 | 22 ± 2 | 63 | 3 ± 0.8 | 7 | 20 ± 2 | 49 | 18 ± 2 | 44 |
Incubations of 13-cRA or 9-cRA (3.3 μM) were with RCH (1.1 mg protein/ml) in 0.1 M sodium phosphate buffer (pH 7.5) and were conducted at 37°C in the dark. Final volumes of the reaction mixtures were 1 ml. Values are expressed as means ± SD of four experimental measurements. For additional details, see Materials and Methods.
↵2-a Retinoic acids in 0.1-ml aliquots of incubation mixtures.
↵2-b Percentage of retinoic acid in total retinoic acids measured by HPLC.
↵2-c ND, values were below the detection limit (1 ng/100 μl).