Gene cloning and expression of MAP30 in .

MAP30, a single-stranded type-I ribosome inactivating protein found in , shows anti-HIV and anti-tumour activity. It could significantly inhibit the HIV-1 and herpes simplex virus infection. In this study, we tried a safe and convenient expression system supplying MAP30 protein for medical practice. The gene encoding MAP30 was cloned into pMD18-T vector. The pMD18-30 plasmid was transformed into competent JM109 by a chemical method. The 30 gene was obtained from the pMD18-30 plasmid digested with I and I and the 30 gene was ligated into pGAPHα. Then, pGAPHα-30 was transformed into GS115 by electroporation. GS115 transformants were analysed by sodium dodecyl sulfate polyacrylamide gelelectrophoresis (SDS-PAGE) and Western blot. SDS-PAGE revealed an extra band of approximately 32 kDa in the supernatant protein of the GS115 transformants and in their intracellular protein fraction. The result of Western-blot analysis showed that the supernatant and the cell pellet from GS115 with pGAPHα-30 could specially bind to monoclonal antibodies against His in the 32 kDa site. These results demonstrated that the expression of MAP30 in was successful; the process of the expression did not need methanol induction or introduction of an antibiotic-resistance gene. The study may provide a new way for MAP30 synthesis. Owing to its safety, this new approach is expected to be widely used in the medical field.