Synthesis, Cloning, and Sequencing of a Codon Optimized Variant of Proteinase Inhibitor II Designed for Expression in Escherichia Coli

Proteinase Inhibitor II (PI2) is a potato tuber peptidase with many potential applications including pest control, radiation protection, and hunger suppression. Recombinant production using Escherichia coli represents a cost-effective approach to produce PI2. In this study, we designed a variant of the pi2 gene designed for expression in E. coli by removal of an intron sequence and optimization of codon usage. The 492 base pair nucleotide sequence termed synPI2 was synthesized and subcloned it into vector pCR2.1-TOPO-TA. The nucleotide sequence of synPI2 was confirmed. The subcloned pi2 in plasmid pCR2.1-TOPO-TA-PI2 is flanked by several restriction enzyme cut sites and can be easily used to cloned the gene into protein expression vectors such as pET32a in future studies.