Recovery of purified animal growth hormone

PURPOSE: To obtain a purified animal growth hormone in a high yield by expressing a plasmid encoding an animal growth hormone or a polypeptide having the same amino acid sequence as the hormone and subsequently subjecting the expression product to a gel filtration chromatography and ion exchange chromatography. CONSTITUTION: This method for recovering a purified animal growth hormone comprises expressing a plasmid encoding the animal growth hormone or a polypeptide analogue having the same amino acid sequence as the animal growth hormone and having its biological activity in bacterial cells, crushing the cell walls of the cells in a buffer solution having a neutral pH, recovering the precipitated genetic product, suspending the product in distilled water, treating the precipitate-containing suspension with an aqueous sodium hydroxide solution to solubilize the precipitates, subjecting the treated product to gel filtration chromatography to separate the solubilized hormone or the polypeptide analogue from other soluble components, and subsequently subjecting the hormone or the polypeptide analogue to ion exchange chromatography, thereby recovering the purified animal growth hormone or its polypeptide analogue in a high yield. COPYRIGHT: (C)1995,JPO