Abstract: Fusion proteins are obtained in high yields if a mixed oligonucleotide is constructed which codes for the ballast constituent of the fusion protein. The oligonucleotide mixture is introduced in a vector in such a manner that it is functionally linked to a regulatory region and to the structural gene for the desired protein. Appropriate host cells are transformed with the plasmid population obtained in this manner and the clones producing a high yield of coded fusion protein are selected.

Abstract: A gene and gene structure coding for an aminotransferase, and microorganisms which express this gene The preparation of L-2-amino-4-methylphosphinobutyric acid (L-PPT) by transamination of (3-carboxy-3-oxopropyl)-methylphosphinic acid with the aid of the L-PPT-specific transaminase from E. coli DH 1 is very much more efficient when the gene coding for this enzyme is isolated, incorporated into a plasmid and then a microorganism is transformed therewith.

Abstract: Compounds of the formula ##STR1## are phosphorylating reagents which react with acylatable hydrogen atoms with elimination of the amine HNR.sup.3 R.sup.4. The resulting compounds are oxidized to give the corresponding phosphate, thiophosphate or selenophosphate derivatives, and the radicals R.sup.1 and R.sup.2 are then split off by means of bases. The chemical nature of the radicals R.sup.1, R.sup.2, R.sup.3 and R.sup.4 accordingly depends on the requirements for these cleavage reactions.

Abstract: Partial sequences of human-.gamma.-interferon, comprising aminoacid sequences 5 to 127, 1 to 127 and 5 to 146, having biological activity. These partial sequences can be obtained by a genetic engineering process, for which purpose the appropriate DNA sequences are chemically synthesized. The DNA sequences are incorporated in hybrid plasmids, and the latter are introduced into host organisms and their expression is induced there. The biologically active polypeptides are suitable, as is human-.gamma.-interferon, for medicaments.

Abstract: Secretin, which cannot be prepared directly by genetic engineering because of its carboxylic acid carboxyl-terminus, can be obtained by preparing secretylglycine by genetic engineering and then obtaining secretin therefrom by enzymatic conversion of the terminal glycine radical. The gene for the secretylglycine is synthesized chemically from smaller single-stranded units which are linked enzymatically to give the complete gene, incorporated into a suitable vector and amplified therein, after which the peptide is isolated directly or as a fusion protein and, after cyanogen bromide cleavage, is converted enzymatically into secretin.