sr-(Octapeptide-53 sh-Polypeptide-47) is a single chain recombinant peptide, produced by fermentation in E. coli. The starting gene is synthesized by the fusion of the gene from Octapeptide-53 and sh-Polypeptide-47. The fusion peptide contains 347 amino acids which may contain disulfide bonds and/or glycosylation and consists of the proper sequence of the 20 standard amino acids.