| abstract |
PURPOSE:To provide a DNA containing a gene coding the surface antigen precursor of an adw-type hepatitis virus B (HBV), useful for transforming animal cell, and producing HBV surface antigen (HBsAg) protein using said cell. CONSTITUTION:The Dane's particle DNA of an adw-type HBV having a single chain at a part thereof is converted to the complete double-chain structure, and bonded by using EcoRI with pBR322 incised by the same EcoRI enzyme. Escherichia coli is transformed by using the bonded product, cultured, and extracted to obtain the plasmid pBR322-EcoRI/HBV933 having HBV DNA. A straight chain HBV DNA is obtained from the plasmid, cyclized, incised with TaqI, and bonded with a fragment obtained by incising pBR322 with ClaI. The bonded product is integrated in the cell of Escherichia coli, the cell is cultured in a conventional medium, and the plasmid is extracted therefrom. The cell of Escherichia coli containing said bonded product is differentiated and cultured, and the bonded product is separated from the cell, purified, and incised with e.g. TaqI. The objective DNA containing preHBsAg gene can be obtained by removing pBR322 from the above product. |