FIGURE 4.

Enzyme activities of Poptr1, Poptr2, Poptr3, and Poptr5 at saturating substrate concentrations (5 mm). Either shikimate (SA) or quinate (QA) was used in conjunction with NAD⁺ (D) or NADP⁺ (P). Cofactor formation (NADH or NADPH) was measured spectrophotometrically at 340 nm and converted to dehydrogenase activities. Both SDH and QDH activities were determined in triplicate; error bars denote standard deviations. Assays yielding less than 0.02 ΔA₃₄₀/min are indicated as not detectable (nd).