Table 1. Structure–activity comparisons of flavones on RepA ATPase activity.
Flavones | Substitutions | Residual ATPase activity (percentage of control) | |||||||
---|---|---|---|---|---|---|---|---|---|
3 | 5 | 7 | 8 | 2′ | 3′ | 4′ | 5′ | ||
Reactions were performed in buffer A as described in the Materials and Methods using 80 nM RepA protein, 100 nM (dT)20 800 µM ATP and 250 µM of the flavone compounds (dimyricetin 50 µM) in buffer A. ATPase activity is expressed relative to activity without inhibitor. OCH3 indicates methoxy substitutions. | |||||||||
Apigenin |
|
|
OH |
|
|
|
OH |
OH |
>95 |
Galangin |
OH |
OH |
OH |
|
|
|
|
|
>95 |
Luteolin |
|
OH |
OH |
|
|
OH |
OH |
|
5 |
Hydroxyflavonea |
|
|
OH |
OH |
|
OH |
OH |
|
50 |
Morin |
OH |
OH |
OH |
|
OH |
|
OH |
|
5 |
Quercetin |
OH |
OH |
OH |
|
|
OH |
OH |
|
>90 |
Trimethyletherb |
OH |
OH |
OH |
|
|
OCH3 |
OCH3 |
OCH3 |
>95 |
Myricetin |
OH |
OH |
OH |
|
|
OH |
OH |
OH |
10 |
Dimyricetin | OH | OH | OH | OH | OH | OH | 2 |
a3′,4′,7,8-Tetrahydroxyflavone.
bMyricetin trimethylether.