Accumulation of Squalene in a Microalga Chlamydomonas reinhardtii by Genetic Modification of Squalene Synthase and Squalene Epoxidase Genes
Fig 1
Functional characterization of CrSQS in E. coli.
A) SDS-polyacrylamide gel electrophoresis of crude extracts from cells harboring the empty vector pET-21b (lane 1), cells expressing CrSQS (lane 2) and purified CrSQS using a TALON Metal affinity chromatography. B) Normal-phase thin-layer chromatogram of the reaction products derived from (1–14C) farnesyl diphosphate (FPP). Crude extracts from cells harboring the empty vector (lanes 1–3), from cells expressing CrSQS (lanes 4–6) and purified CrSQS protein (lanes 7–9) were assayed for SQS activity using (1–14C) FPP and Mg2+ with NADPH (lanes 1–2, 4–5, and 7–8 are experimental replicates) or without NADPH (lanes 3, 6, 9). Authentic (1–14C) FPP was loaded in lane 10 as a negative control. The positions of origin, solvent front and authentic squalene are indicated on the left. Open triangles on the right indicate position of signals from putative dehydrosqualene and 12-hydroxysqualene in lane 9.