sr-(Methionyl s-Rainbow Trout Oligopeptide-1 sh-Polypeptide-4 Hexapeptide-40) is a single chain recombinant peptide, produced by fermentation in E. coli. The starting gene is synthesized by the fusion of the gene from s-Rainbow Trout Oligopeptide-1, sh-Polypeptide-4, and Hexapeptide-40, with the initiation code for methionine. The fusion peptide contains 184 amino acids which may contain disulfide bonds and/or glycosylation, and consists of the proper sequence of the 20 standard amino acids.