Table 2.
Substrate Preferences and Relative Activities of AAGTs for Various Acceptor Molecules
| nkat/mg Protein (Relative Activities [%]) | |||
| Substrates | Native Dc AA5GT | Recombinant Dc AA5GT | Recombinant Dg AA7GT |
| Flavonoids | |||
| Kaempferol | ND | ND | ND |
| Kaempferol 3-glucoside | ND | ND | ND |
| Apigenin | ND | ND | ND |
| Apigenin 7-glucoside | ND | ND | ND |
| Naringenin | ND | ND | ND |
| Naringenin 7-glucoside | ND | ND | ND |
| Cyanidin | ND | ND | ND |
| Cyanidin 3-glucoside | 0.34 ± 0.04 (100) | 0.76 ± 0.09 (100) | 1.02 ± 0.08 (100) |
| Cyanidin 3-galactoside | 0.43 ± 0.06 (126) | 0.90 ± 0.01 (119) | 0.60 ± 0.02 (59) |
| Cyanidin 3-malylglucoside | 0.4 ± 0.1 (128) | 1.0 ± 0.2 (131) | 0.44 ± 0.06 (43) |
| Cyanidin 3,5-diglucoside | ND | ND | ND |
| Cyanidin 3,7-diglucoside | ND | ND | ND |
| Pelargonidin | ND | ND | ND |
| Pelargonidin 3-glucoside | 0.45 ± 0.07 (131) | 1.4 ± 0.3 (181) | 1.00 ± 0.03 (98) |
| Pelargonidin 3-malylglucoside | 0.35 ± 0.03 (101) | 0.82 ± 0.08 (108) | 0.24 ± 0.03 (24) |
| Delphinidin | ND | ND | ND |
| Delphinidin 3-glucoside | 0.52 ± 0.03 (152) | 0.89 ± 0.06 (117) | 1.73 ± 0.24 (170) |
| (+) Catechin | ND | ND | ND |
| (−) Epicatechin | ND | ND | ND |
| Naphthols | |||
| 1-Naphtol | ND | ND | ND |
| 2-Naphtol | ND | ND | ND |
| NAA | ND | ND | ND |
| IAA | ND | ND | ND |
| Coumarins | |||
| 7-Hydroxy-4-methylcoumarin | ND | ND | ND |
| 7-Hydroxy-6-methoxycoumarin | ND | ND | ND |
| Phenols | |||
| Salicylic acid | ND | ND | ND |
| Phloroglucin | ND | ND | ND |
Acceptor preferences of AAGT proteins using 1-O-β-d-vanillyl-glucose as the donor. Relative activity is shown in comparison to Cy3G, which is arbitrarily set as 100%. IAA, indole-3-acetic acid; NAA, naphthalene-1-acetic acid; ND, not detectable. All values are the mean ± sd at least three independent determinations.