Peptides

thumb|Drosomycin, an example of a peptide

Desmopressin, sold under the trade name Ddavp among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels. In hemophilia A and von Willebrand disease, it should only be used for mild to moderate cases. It may be given in the nose, by injection into a vein, by mouth, or under the tongue.

Hirudin is a naturally occurring peptide in the salivary glands of blood-sucking leeches (such as Hirudo medicinalis) that has a blood anticoagulant property. This is essential for the leeches' habit of feeding on blood, since it keeps a host's blood flowing after the worm's initial puncture of the skin.

group of peptides, several of which can form oligomeric cation-selective peptide channels

thumb|425x170 px|Left: Unbound aptamer. Right: the aptamer bound to its target protein. The protein is in yellow. Parts of the aptamer that change shape when it binds its target are in blue, while the unchanging parts are in orange. The parts of the aptamer that contact the protein are highlighted in red.

Enfuvirtide (INN), sold under the brand name Fuzeon, is an HIV fusion inhibitor, the first of a class of antiretroviral drugs used in combination therapy for the treatment of AIDS/HIV.

The connecting peptide, or C-peptide, is a short 31-amino-acid polypeptide that connects insulin's A-chain to its B-chain in the proinsulin molecule. In the context of diabetes or hypoglycemia, a measurement of C-peptide blood serum levels can be used to distinguish between different conditions with similar clinical features.

thumb|300px|A tripeptide (example Valine|Val-Gly-Ala) with green marked amino end (L-Valine) and blue marked carboxyl end (L-Alanine) thumb|300px|A tetrapeptide (example Valine|Val-Gly-Ser-Ala) with green marked amino end (L-valine) and blue marked carboxyl end (L-alanine) An oligopeptide (oligo-, "a few"), is a peptide consisting of two to twenty amino acids, including dipeptides, tripeptides, tetrapeptides, and other polypeptides. Some of the major classes of naturally occurring oligopeptides include aeruginosins, cyanopeptolins, microcystins, microviridins, microginins, anabaenopeptins, and

Bivalirudin, sold under the brand names Angiomax and Angiox, among others, is a specific and reversible direct thrombin inhibitor (DTI). Chemically, it is a synthetic congener of the naturally occurring drug hirudin, found in the saliva of the medicinal leech Hirudo medicinalis. It is manufactured by The Medicines Company.

Terlipressin, sold under the brand name Terlivaz among others, is an analogue of vasopressin used as a vasoactive drug in the management of low blood pressure. It has been found to be effective when norepinephrine does not help. Terlipressin is a vasopressin receptor agonist.

Ziconotide, sold under the brand name Prialt, also called intrathecal ziconotide (ITZ) because of its administration route, is an atypical analgesic agent for the amelioration of severe and chronic pain. Derived from Conus magus, a cone snail, it is the synthetic form of an ω-conotoxin peptide.

Alitame is an aspartic acid-containing dipeptide sweetener. It was developed by Pfizer in the early 1980s and currently marketed in some countries under the brand name Aclame. Most dipeptides are not sweet, but the unexpected discovery of aspartame in 1965 led to a search for similar compounds that shared its sweetness.

Kallidin belongs to the family kinins, which are the peptide hormones. Kallidin is a decapeptide whose sequence is H-Lys-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg-OH. Removal of the N-terminal lysine by Factor XII, or to a leser extent aminopeptidase yields the potently bioactive bradykinin molecule.

thumb|300px|A tripeptide (example Valine|Val-Gly-Ala) with green marked amino end (L-Valine) and blue marked carboxyl end (L-Alanine)

class of peptide secondary metabolites, usually produced by microorganisms like bacteria and fungi

chemical compound

planned process in synthetic organic chemistry

Procalcitonin (PCT) is a peptide precursor of the hormone calcitonin, the latter being involved with calcium homeostasis. It arises once preprocalcitonin is cleaved by endopeptidase. It was first identified by Leonard J. Deftos and Bernard A. Roos in the 1970s. It is composed of 116 amino acids and is produced by parafollicular cells (C cells) of the thyroid and by the neuroendocrine cells of the lung and the intestine.

Tesamorelin (INN; trade name Egrifta SV) is a synthetic form of growth-hormone-releasing hormone (GHRH) which is used in the treatment of HIV-associated lipodystrophy, approved initially in 2010. It is produced and developed by Theratechnologies, Inc. of Canada. The drug is a synthetic peptide consisting of all 44 amino acids of human GHRH with the addition of a trans-3-hexenoic acid group.

Nesiritide, sold under the brand name Natrecor, is the recombinant form of the 32 amino acid human B-type natriuretic peptide, which is normally produced by the ventricular myocardium. Nesiritide works to facilitate cardiovascular fluid homeostasis through counterregulation of the renin–angiotensin–aldosterone system, stimulating cyclic guanosine monophosphate, leading to smooth muscle cell relaxation.

Pasireotide, sold under the brand name Signifor, is an orphan drug approved in the United States and the European Union for the treatment of Cushing's disease in patients who fail or are ineligible for surgical therapy. It was developed by Novartis. Pasireotide is a somatostatin analog with a 40-fold increased affinity to somatostatin receptor 5 compared to other somatostatin analogs.

Atosiban, sold under the brand name Tractocile among others, is an inhibitor of the hormones oxytocin and vasopressin. It is used as an intravenous medication as a labour repressant (tocolytic) to halt premature labor. It was developed by Ferring Pharmaceuticals in Sweden and first reported in the literature in 1985. Originally marketed by Ferring Pharmaceuticals, it is licensed in proprietary and generic forms for the delay of imminent preterm birth in pregnant adult women.

Pentagastrin (trade name Peptavlon) is a synthetic polypeptide that has effects like gastrin when given parenterally. It stimulates the secretion of gastric acid, pepsin, and intrinsic factor, and has been used as a diagnostic aid as the pentagastrin-stimulated calcitonin test.

Ganirelix acetate (or diacetate), sold under the brand names Orgalutran and Antagon among others, is an injectable competitive gonadotropin-releasing hormone antagonist (GnRH antagonist). It is primarily used in assisted reproduction to control ovulation. The drug works by blocking the action of gonadotropin-releasing hormone (GnRH) upon the pituitary, thus rapidly suppressing the production and action of LH and FSH. Ganirelix is used in fertility treatment to prevent premature ovulation that could result in the harvesting of eggs that are too immature to be used in procedures such as in vitro

Teduglutide, sold under the brand names Revestive (EU) and Gattex (US), is a 33-membered polypeptide and glucagon-like peptide-2 (GLP-2) analog that is used for the treatment of short bowel syndrome. It works by promoting mucosal growth and possibly restoring gastric emptying and secretion. It was approved in both the European Union and the United States in 2012.

Afamelanotide, sold under the brand name Scenesse, is a medication used to prevent phototoxicity and to reduce pain from light exposure for people with erythropoietic protoporphyria. It is a melanocortin 1 receptor (MC1 receptor) agonist and a synthetic peptide and analogue of α-melanocyte stimulating hormone. It is administered as subcutaneous implant.

protein-coding gene in the species Homo sapiens

Amanin is a cyclic peptide. It is one of the amatoxins, all of which are found in several members of the mushroom genus Amanita.

Apamin is an 18 amino acid globular peptide neurotoxin found in apitoxin (bee venom). Dry bee venom consists of 2–3% of apamin. Apamin selectively blocks SK channels, a type of Ca2+-activated K+ channel expressed in the central nervous system. Toxicity is caused by only a few amino acids, in particular cysteine1, lysine4, arginine13, arginine14 and histidine18. These amino acids are involved in the binding of apamin to the Ca2+-activated K+ channel. Due to its specificity for SK channels, apamin is used as a drug in biomedical research to study the electrical properties of SK channels and thei

Ferrichrome is a cyclic hexa-peptide that forms a complex with iron atoms. It is a siderophore composed of three glycine and three modified ornithine residues with hydroxamate groups [-N(OH)C(=O)C-]. The 6 oxygen atoms from the three hydroxamate groups bind Fe(III) in near perfect octahedral coordination.

thumb|right|350px|Casomorphin#Bovine β-casomorphin 7|Bovine β-casomorphin 7, a casomorphin, has seven amino acids in its [[peptide sequence.]] Casomorphin is an opioid peptide (protein fragment) derived from the digestion of the milk protein casein.

thumb|300px|Structure of the methanofurans

Amanullin is a cyclic peptide. It is an amatoxin, all of which are found in several members of the mushroom genus Amanita. The oral of amanullin is approximately 20 mg/kg in mice; however, it is non-toxic in humans.

peptide in Homo sapiens

Pyoverdines (alternatively, and less commonly, spelled as pyoverdins) are fluorescent siderophores produced by certain pseudomonads. Pyoverdines are important virulence factors, and are required for pathogenesis in many biological models of infection. Their contributions to bacterial pathogenesis include providing a crucial nutrient (i.e., iron), regulation of other virulence factors (including exotoxin A and the protease PrpL), supporting the formation of biofilms, and are increasingly recognized for having toxicity themselves.

Trypanothione is an unusual form of glutathione containing two molecules of glutathione joined by a spermidine (polyamine) linker. It is found in parasitic protozoa such as leishmania and trypanosomes. These protozoal parasites are the cause of leishmaniasis, sleeping sickness and Chagas' disease. Trypanothione was discovered by Alan Fairlamb. Its structure was proven by chemical synthesis. It is present mainly in the Kinetoplastida but can be found in other parasitic protozoa such as Entamoeba histolytica. Since this thiol is absent from humans and is essential for the survival of the parasit

chemical compound (group of stereoisomers)

thumb|300px|A tetrapeptide (example Valine|Val-Gly-Ser-Ala) with green marked amino end (L-Valine) and blue marked carboxyl end (L-Alanine). A tetrapeptide is a peptide, classified as an oligopeptide, since it only consists of four amino acids joined by peptide bonds. Many tetrapeptides are pharmacologically active, often showing affinity and specificity for a variety of receptors in protein-protein signaling. Present in nature are both linear and cyclic tetrapeptides (CTPs), the latter of which mimics protein reverse turns which are often present on the surface of proteins and druggable targe

Proinsulin is the prohormone precursor to insulin made in the beta cells of the Pancreatic Islets, specialized regions of the pancreas. In humans, proinsulin is encoded by the INS gene. The pancreatic islets only secrete between 1% and 3% of proinsulin intact. However, because proinsulin has a longer half life than insulin, it can account for anywhere from 5–30% of the insulin-like structures circulating in the blood. There are higher concentrations of proinsulin after meals and lower levels when a person is fasting. Additionally, while proinsulin and insulin have structural differences, proin

Urodilatin (URO) is a hormone that causes natriuresis by increasing renal blood flow. It is secreted in response to increased mean arterial pressure and increased blood volume from the cells of the distal tubule and collecting duct. It is important in oliguric patients (such as those with acute kidney injury and chronic kidney failure) as it lowers serum creatinine and increases urine output.

Cerebrolysin (developmental code name FPF-1070) is an experimental mixture of enzymatically-treated peptides derived from pig brain whose constituents can include brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), nerve growth factor (NGF), and ciliary neurotrophic factor (CNTF). Although it is under preliminary study for its potential to treat various brain diseases, it is used as a therapy in dozens of countries in Eurasia.

Voclosporin, sold under the brand name Lupkynis, is a calcineurin inhibitor used as an immunosuppressant medication for the treatment of lupus nephritis. It is an analog of ciclosporin that has enhanced action against calcineurin and greater metabolic stability.

Pepstatin is a potent inhibitor of aspartyl proteases. It is a hexa-peptide containing the unusual amino acid statine (Sta, (3S,4S)-4-amino-3-hydroxy-6-methylheptanoic acid), having the sequence Isovaleryl-Val-Val-Sta-Ala-Sta (Iva-Val-Val-Sta-Ala-Sta). It was originally isolated from cultures of various species of Actinomyces due to its ability to inhibit pepsin at picomolar concentrations. It was later found to inhibit nearly all acid proteases with high potency and, as such, has become a valuable research tool, as well as a common constituent of protease inhibitor cocktails.

mammalian protein found in Homo sapiens

Saralasin is a competitive angiotensin II receptor antagonist with partial agonistic activity. The aminopeptide sequence for saralasin differs from angiotensin II at three sites: At position 1, sarcosine replaces aspartic acid, thereby increasing the affinity for vascular smooth muscle AT II receptors and making sara resistant to degradation by aminopeptidases. At position 5, isoleucine is replaced by valine At position 8, phenylalanine is replaced by alanine which leads to a smaller stimulatory effect. Saralasin was used to distinguish renovascular hypertension from essential hypertension

Amaninamide is a cyclic peptide. It is one of the amatoxins, all of which are found in several members of the mushroom genera Amanita, Lepiota and Galerina. It differs from alpha-amanitin in lacking the hydroxyl group on tryptophan. This alters its UV absorption spectrum but not its toxicity.

protein-coding gene in the species Homo sapiens

chemical compound

Promanullin is a cyclic nonribosomal peptide. It is an amatoxin, all of which are found in the mushroom genus Amanita.

mammalian protein found in Homo sapiens

thumb|right|200px|Two subunits of cyanophycin with alternating directionality. Cyanophycin, also known as CGP (cyanophycin granule polypeptide) or multi-L-arginyl-poly (L-aspartic acid), is a non-protein, non-ribosomally produced amino acid polymer composed of an aspartic acid backbone and arginine side groups.

Etelcalcetide, sold under the brand name Parsabiv, is a calcimimetic medication for the treatment of secondary hyperparathyroidism in people undergoing hemodialysis. It is administered intravenously at the end of each dialysis session. Etelcalcetide functions by binding to and activating the calcium-sensing receptor in the parathyroid gland. Parsabiv is currently owned by Amgen and Ono Pharmaceuticals in Japan.

A microantibody is an artificial short chain of amino acids copied from a fully functional natural antibody. Microantibodies can stop viruses such as HIV from infecting cells in vitro.

Slotoxin is a peptide from Centruroides noxius Hoffmann scorpion venom. It belongs to the short scorpion toxin superfamily.

Sermorelin acetate (; brand names Geref, Gerel), also known as GHRH (1-29), is a peptide analogue of growth hormone-releasing hormone (GHRH) which is used as a diagnostic agent to assess growth hormone (GH) secretion for the purpose of diagnosing growth hormone deficiency. It is a 29-amino acid polypeptide representing the 1–29 fragment from endogenous human GHRH, thought to be the shortest fully functional fragment of GHRH.

Dasiglucagon, sold under the brand name Zegalogue, is a medication used to treat severe hypoglycemia in people with diabetes.

Ceruletide (INN), also known as cerulein or caerulein, is a ten amino acid oligopeptide that stimulates smooth muscle and increases digestive secretions. Ceruletide is similar in action and composition to cholecystokinin. It stimulates gastric, biliary, and pancreatic secretion; and certain smooth muscle. It is used in paralytic ileus and as diagnostic aid in pancreatic malfunction. It is used to induce pancreatitis in experimental animal models.

Alisporivir (INN), or Debio 025, DEB025, (or UNIL-025) is a cyclophilin inhibitor. Its structure is reminiscent of and synthesized from ciclosporin.

thumb|300px|Chemical structure of phytochelatin. n = 2–11.