sh-Polypeptide-64 is a single chain synthetic human peptide, produced by fermentation in E. coli. The starting gene is a synthesized copy of the human gene which codes for Aquaporin-1 used as such or adapted to the production host. It contains a maximum of 269 amino acids which may contain disulfide bonds and/or glycosylation. The protein consists of the proper sequence of the 20 standard amino acids.