Table 1.

Enzymatic activities of the purified recombinant PlOMT4 toward a range of substrates in vitro.

Substrate	Enzyme activity (pkat/mg)	Relative activity (%)a
Phenolic acid
Caffeic acid	0	0
Isoflavone
3′-Hydroxy-daidzein	4180.4 ± 150.5	100 ± 3.6
Daidzein	0	0
Genistein	0	0
Formononetin	0	0
Biochanin A	0	0
Prunetin	0	0
Isoformononetin	0	0
Chalcone
Isoliquiritigenin	0	0
Flavone
Apigenin	0	0
Luteolin	1759.9 ± 142.1	42.1 ± 3.4
Flavanone
Liquiritigenin	0	0
Flavonol
Quercetin	1142.3 ± 54.4	27.3 ± 1.3
Kaempferol	0	0

^aRelative activity. The values are normalized with the most converted substrate 3′-hydroxy-daidzein as 100%.