Table 1. Kinetic Parameters of AtCPT7 with GPP, FPP, or GGPP as Substrate.

Substrate	Km (µM)	Kcat (s−1)	Kcat/Km (s−1 M−1)
GPP	43.91 ± 11.35	0.106 ± 0.008	2.41 × 103
FPP	3.83 ± 0.72	0.104 ± 0.004	2.70 × 104
GGPP	5.87 ± 0.91	0.109 ± 0.004	1.85 × 104

Measurements were made at room temperature in 50 mM HEPES buffer, pH 8.0, containing, 5 mM DTT, 7.5 mM MgCl₂, 100 mM KCl, 10% (v/v) glycerol, and 0.1% (v/v) Triton X-100. Reactions were started by adding ¹⁴C-IPP substrate. Data are the means of three independent determinations ± sd.