Dermorphin is a hepta-

peptide Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. A ...

first isolated from the skin of South American

frog A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...

s belonging to the genus ''

Phyllomedusa ''Phyllomedusa'' is a genus of tree frogs in the subfamily Phyllomedusinae found in tropical and subtropical South America (south to northern Argentina) and Panama. It has 16 recognised species. Taxonomy The following species are recognised i ...

''. The peptide is a natural

opioid Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid us ...

that binds as an

agonist An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ago ...

with high potency and selectivity to mu Opioid receptors. Dermorphin is about 30–40 times more potent than

morphine Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...

but theoretically may be less likely to produce

drug tolerance Drug tolerance or drug insensitivity is a pharmacological concept describing subjects' reduced reaction to a drug following its repeated use. Increasing its dosage may re-amplify the drug's effects; however, this may accelerate tolerance, further ...

and

addiction Addiction is a neuropsychological disorder characterized by a persistent and intense urge to engage in certain behaviors, one of which is the usage of a drug, despite substantial harm and other negative consequences. Repetitive drug use o ...

(due to its high potency). The amino acid sequence of dermorphin is H-Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH₂. Dermorphin is not found in humans or other mammals and similar D-

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...

peptides have only been found in

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...

amphibian Amphibians are tetrapod, four-limbed and ectothermic vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terres ...

s and molluscs. Dermorphin appears to be made in these through an unusual

posttranslational modification Post-translational modification (PTM) is the covalent and generally enzymatic modification of proteins following protein biosynthesis. This process occurs in the endoplasmic reticulum and the golgi apparatus. Proteins are synthesized by ribosome ...

carried out by an amino acid isomerase. This unusual process is needed because the D-alanine in this peptide is not among the 20 amino acids coded for in the genetic code and thus the peptide cannot be synthesized in the usual way from the encodings in the

genome In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding ge ...

of an

organism In biology, an organism () is any living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy into groups such as multicellular animals, plants, and ...

Illicit use

Dermorphin has been illegally used in

horse racing Horse racing is an equestrian performance sport, typically involving two or more horses ridden by jockeys (or sometimes driven without riders) over a set distance for competition. It is one of the most ancient of all sports, as its basic p ...

as a performance-enhancing drug. Due to dermorphin's painkilling activity, horses treated with dermorphin may run harder than they would otherwise.

References

{{Opioidergics Mu-opioid receptor agonists Opioid peptides

Illicit use

See also

References