Abstract: Novel rapid-acting human insulin analogues are provided having less tendency to self-association into dimers, tetramers, hexamers, or polymers. The novel human insulin analogues are formed by substituting one or more of the amino acid residues of human insulin with naturally occuring amino acid residues. The amino acid residue substitutions are preferably more hydrophilic than the natural amino acid residue at the respective position in the molecule. Furthermore, the insulin analogues have the same charge or a greater negative charge at neutral pH than that of human insulin. Preferred amino acid substitutions are Asp, Glu, Ser, Thr, His, and Ile, and more preferred substitutions are Asp and Glu. The novel insulin analogues can be used for the preparation of rapid-acting insulin solutions.

Abstract: Human insulin precursors containing the peptide chain B(1-29)-A(1-21) of human insulin and derivatives thereof with a bridging chain connecting the carboxyl terminus of the B(1-29)-chain with the amino terminus of the A(1-21)-chain are prepared by culturing a yeast host transformed with a replicable expression vehicle capable of expressing a DNA-sequence encoding the insulin precursor. The bridging chain is preferably relatively short and contains preferably from 2 to 8 amino acid residues. The bridging chain must not contain two adjacent basic amino acid residues (Lys or Arg) and has one Lys or Arg connected to the amino terminus of the A(1-21)-chain. Human insulin is prepared from the insulin precursors by in vitro conversion.

Abstract: Glucagon or fragments or derivatives thereof are prepared by cultivation of a yeat strain transformed with a replicable expression vehicle comprising a gene encoding the expression of such products. Synthetic genes encoding glucagon or derivatives thereof have been constructed. Also provided are replicable expression vehicles comprising a replication system for providing stable maintenance in yeast and a DNA-sequence encoding glucagon or fragments or derivatives thereof and transformant yeast strains containing such expression vehicles.