Figure 5.

Thin layer chromatograms of the reaction products obtained from pyruvate and d-glyceraldehyde or dl-glyceraldehyde 3-phosphate. Cell-free extracts from induced E. coli XL1-Blue cells harboring plasmid pTAC-ORF2 (25 μg of protein) were incubated for 2 h under the conditions described in Materials and Methods with the following substrates: pyruvate and d-glyceraldehyde (lanes 2 and 5) and pyruvate and dl-glyceraldehyde 3-phosphate (lanes 3 and 4). The reactions were stopped, and reaction mixture aliquots (10 μl) were treated with 1.25 units of calf intestine alkaline phosphatase for 1 h (lanes 4 and 5). Lane 1 corresponds to a standard of chemically synthesized d-1-deoxyxylulose. Reaction products were detected by staining with p-anisaldehyde/sulfuric acid. The positions of d-1-deoxyxylulose (1-DX) and d-1-deoxyxylulose 5-phosphate (1-DX-5-P) are indicated.