Figure 1.

Oligonucleotide sets used to build the synthetic genes. Internal repeat oligonucleotide sets encoding Ser-Pro repeats or the gum arabic glycoprotein (GAGP) sequence were polymerized head-to-tail in the presence of the 5′ linker set. After ligation, the 3′ linker was added, and the genes were then restricted with BamHI and EcoRI and inserted into pBluescript II SK(+). The signal sequence was built by primer extension of the overlapping oligonucleotides featured here. The overlap is underlined.