Oligopeptide classes are produced bynonribosomal peptides synthases (NRPS), except cyclamides and microviridins are synthesized throughribosomic pathways.[3]
Amanitins - Cyclic peptides taken from carpophores of several different mushroom species. They are potent inhibitors ofRNA polymerases in most eukaryotic species, the prevent the production of mRNA and protein synthesis. These peptides are important in the study of transcription. Alpha-amanitin is the main toxin from the speciesAmanita phalloides, poisonous if ingested by humans or animals.
Antipain - An oligopeptide produced by various bacteria which acts as aprotease inhibitor.
Ceruletide - A specific decapeptide found in the skin ofHyla caerulea, theAustralian green tree frog. Ceruletide has very much in common with regards to action and composition tocholecystokinin. It stimulates gastric, biliary, and pancreatic secretion; and certainsmooth muscle. It is used to inducepancreatitis in experimental animal models.
Glutathione - A tripeptide with many roles in cells. It conjugates to drugs to make them more soluble for excretion, is a cofactor for some enzymes, is involved in protein disulfide bond rearrangement and reduces peroxides.
Leupeptins - A group of acylated oligopeptides produced by Actinomycetes that function as protease inhibitors. They have been known to inhibit to varying degreestrypsin,plasmin,kallikreins,papain and thecathepsins.
Netropsin - A basic oligopeptide isolated fromStreptomyces netropsis. It is cytotoxic and its strong, specific binding to A-T areas of DNA is useful to genetics research.
Pepstatins -N-acylated oligopeptides isolated from culture filtrates of Actinomycetes, which act specifically to inhibit acid proteases such as pepsin and renin.
Peptide T -N-(N-(N(2)-(N-(N-(N-(N-D-AlanylL-seryl)-L-threonyl)-L-threonyl)L-threonyl)-L-asparaginyl)-L-tyrosyl)L-threonine. Octapeptide sharingsequence homology with HIV envelope protein gp120. It may be useful as antiviral agent in AIDS therapy. The core pentapeptide sequence, TTNYT, consisting of amino acids 4-8 in peptide T, is the HIV envelope sequence required for attachment to the CD4 receptor.
Phalloidin - A very toxic polypeptide isolated mainly fromAmanita phalloides (Agaricaceae) or death cap; causes fatal liver, kidney and CNS damage in mushroom poisoning; used in the study of liver damage.
Teprotide - A man-made nonapeptide (Pyr-Trp-Pro-Arg-Pro-Gln-Ile-Pro-Pro) which is exactly the same as the peptide from the venom of the snake, Bothrops jararaca. It inhibits kininase II and angiotensin I and has been proposed as an antihypertensive agent.
Tuftsin -N(2)-((1-(N(2)-L-Threonyl)-L-lysyl)-L-prolyl)-L-arginine. A tetrapeptide manufactured in the spleen by enzymatic cleavage of a leukophilic gamma-globulin. It stimulates the phagocytic activity of blood polymorphonuclear leukocytes and neutrophils in particular. The peptide is located in the Fd fragment of the gamma-globulin molecule.
