| 摘要 |
PURPOSE:To purify basic peptide produced by a recombinant microorganism in high purity, by separating basic peptide prepared as fused protein with another polypeptide by cyanogen bromide treatment, subjecting it to column chromatography by cation exchange resin, or gel filtration. CONSTITUTION:Basic peptide from a culture mold of microorganism synthesized by the use of recombinant DNA technique is purified. Namely, the culture mold is treated with formic acid and cyanogen bromide with stirring, formic acid and cyanogen bromide are removed under reduced pressure. The residue is homogenized with an acidic aqueous solution such as an aqueous solution of acetic acid to extract the desired peptide, and the extract is adsorbed on a cation exchange resin packed into a column. The adsorbed substance is eluted with an acidic or basic buffer, and the eluate is adsorbed on a weak cation exchange resin. The adsorbed substance is then eluted with an aqueous solution of an organic ammonium salt, the eluate is subjected to gel filtration, the filtrate is adsorbed on a weak cation exchange resin, eluted with an aqueous solution of organic ammonium salt, to give the desired purified basic peptide. |
