Fig. 5: Effects of CHIL and related proteins on the product specificities of CHS, CTAS, and STS.

a Concentrations of products (blue bars, naringenin; orange bars, CTAL) formed after reactions catalyzed by 0.1 µM AmCHS in the presence and absence of 1 µM AmCHIL or AmCHI. b Concentrations of products (blue bars, naringenin; orange bars, CTAL) formed after reactions catalyzed by 0.1 µM PpCHS in the presence and absence of 1 µM PpCHIL. c Left, Concentrations of products formed after reactions catalyzed by 0.1 µM HmCHS in the presence and absence of 1 µM HmCHIL or HmCHI. Right, Concentrations of products formed after reactions catalyzed by 0.1 µM HmCTAS in the presence and absence of 1 µM HmCHIL or HmCHI. Blue bars, naringenin; orange bars, CTAL. d Left, Concentrations of products formed after reactions catalyzed by 0.1 µM VvCHS in the presence and absence of 1 µM VvCHIL. Right, Concentrations of products formed after reactions catalyzed by VvSTS in the presence and absence of VvCHIL. Blue bars, naringenin; orange bars, CTAL; and pink bars, resvertrol. e E values of reactions catalyzed by CHS (0.1 μM) in the presence (light-orange bars) and absence (gray bars) of homologous CHIL (1 μM) in various land plants. For (a–e), the numbers above panels indicate the relative percentages of the total amount of polyketide products, with the amount obtained in the absence of added CHIL or CHI set at 100%. f Effects of AmCHIL concentrations on the E values of the reaction catalyzed by 0.1 μM AmCHS. g Effects of PpCHIL concentrations on the E values of the reaction catalyzed by 0.1 μM PpCHS. For (a–g), enzymatic reactions were completed essentially under standard assay conditions (see Methods). Data are presented as the average of three independent determinations (±standard deviation). The underlying data for (a–g) are provided in the Source Data file.