s-Black Widow Spider Pentapeptide-1 SP is a single chain protein containing 5 amino acids. It is synthetically produced based on a sequence from Alpha-Latrotoxin-Lt1a, which is found in the black widow spider, Latrodectus tredecimguttatus. The parent protein contains a maximum of 1401 amino acids which may contain disulfide bonds and/or glycosylation, and consists of the proper sequence of the 20 standard amino acids.