Abstract: A structural gene coding for authentic human serum albumin, --optionally supplemented by an upstream triplet coding for methionine and optionally extended by a synthetic prepro.sup.x -leader-coding sequence--, wherein the codons of the nucleotide sequence have been selected with regard to a non-human host, e.g. yeast, chosen for expression of authentic human serum albumin, is disclosed.Additionally there is disclosed a method of producing said gene.There are also disclosed a recombinant DNA molecule comprising said strucural gene inserted into a vector, and a host transformed with said recombinant DNA molecule.Furthermore there are disclosed a method of producing authentic human serum albumin, an authentic human serum albumin resulting from said method, and a pharmaceutical composition comprising said resulting human serum albumin.

Abstract: Disclosed are in vitro active cell growth factors that stimulate deoxyribonucleic acid synthesis in the cells, are polypeptide in chemical structure, having a molecular weight range of from 4,000 to 6,000 and an isoelectric range of from pH 4.3 to 5.3, are inert to about 72% aqueous ethanol containing by volume about 0.047% of concentrated hydrochloric acid, soluble in and precipitated from such acid aqueous ethanol solution by admixing in it 3.5 times its volume of a mixture of five parts of acetone with three parts of ethanol, and are soluble in about twice their weight of 20% formic acid.