Amino-acid Composition of Human Growth Hormone

THE amino-acid composition of a human growth hormone preparation was given by Dixon and Li1 in 1962; and the same year Li, Liu and Dixon also reported2 that human growth hormone purified by a procedure involving chromatography on ‘Amberlite IRC-50’ and ‘Sephadex G-50’ showed the same amino-acid composition. This communication records our findings on the amino-acid analysis of human growth hormone samples prepared by purification on ‘Sephadex G-200’3, a procedure which yields a product with approximately twice the biological activity of the preparations studied by Li et al.