| 摘要 |
PURPOSE:To obtain a new protein, having the antiviral activity derived from Phytolacca americana L., without being influenced by seasons, weather, etc., stably having an in vitro protein synthesis-inhibiting activity comparable to that of lysine and useful as an anti-AIDS medicine, etc. CONSTITUTION:Respective tissues of a seed, a leaf and a root obtained from Phytolacca americana L. are quick frozen with liquid nitrogen, etc., and subsequently powdered with a pulverizer to extract the whole RNA by a guanidine thiocyanate method. The mRNA is extracted by a conventional method and used as a template to prepare a synthetic primer based on a known amino acid sequence. A partial cDNA is then synthesized by a polymerase chain reaction(PCR) method and used as a probe to alone chromosomal DNA library of the Phytolacca americana L. Thereby, a clone containing a DNA capable of coding a protein having antiviral activity of the Phytolacca americana L. is selected. The resultant DNA is subsequently treated with a restriction enzyme, bound to an expression vector and transduced into a host cell to carry out transformation. The obtained transformant is cultured to afford the objective new protein derived from the Phytolacca americana L. |
