FIG. 4.

AtROP is prenylated in TSM and both prenylated and acylated in DRM. Total-ion chromatograms of initial standards are shown (A). Lipids were cleaved from NP-40-soluble purified His₆-GFP-AtROP6 (AtROP6-TSM) (B) and NP-40-insoluble purified His₆-GFP-AtROP6 (AtROP6-DRM) (C) by sequential hydrogenation and Raney nickel cleavage. In TSMs, AtROP6 was only prenylated by geranylgeranyl (B), and in DRM, it was both prenylated by geranylgeranyl and S acylated by palmitic and stearic acids (C). Peaks: 1, 2,6,10-trimethyldodecane, saturated derivative of farnesol; 2, 2,6,10,14-tetramethylhexadecane, saturated derivative of geranylgeraniol; 3, ethyl palmitate, derivative of palmitate formed following hydrogenation; 4, ethyl stearate, derivative of stearate formed following hydrogenation. No lipids were detected following lipid extraction of purified His₆-GFP-Atrop6^CAmS¹⁹⁵ (Atrop6mS¹⁹⁵) (D) or His₆-AtROP6 purified from E. coli cells (E).