FIG. 4.
TLC analysis of products synthesized by M. smegmatis membranes in the presence of [14C]IPP and either DMAPP (A), GPP (B), ω,E,E-FPP (C), or ω,E,E,E-GGPP (D). Assay conditions were as described for Fig. 2. The radiolabeled prenyl diphosphates were dephosphorylated with potato acid phosphatase, and equivalent amounts of radioactivity were analyzed on LKC18F TLC plates developed in methanol-acetone (8:2, vol/vol). Radioactive spots were located with a System 200 Imaging Scanner (Bioscan Inc.), and standard polyprenols were located with an anisaldehyde spray reagent (9).