Antipain is an

oligopeptide An oligopeptide, often just called peptide ('' oligo-'', "a few"), consists of two to twenty amino acids and can include dipeptides, tripeptides, tetrapeptides, and pentapeptides. Some of the major classes of naturally occurring oligopeptides in ...

that is isolated from

actinomycetes The Actinomycetales is an order of Actinomycetota. A member of the order is often called an actinomycete. Actinomycetales are generally gram-positive and anaerobic and have mycelia in a filamentous and branching growth pattern. Some actinomycete ...

and used in biochemical research as a protease inhibitor of

trypsin Trypsin is an enzyme in the first section of the small intestine that starts the digestion of protein molecules by cutting these long chains of amino acids into smaller pieces. It is a serine protease from the PA clan superfamily, found in the di ...

and papain. It was discovered in 1972 and was the first natural peptide found that contained an ureylene group. Antipain can aid in prevention of

coagulation Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The mechanism ...

in blood. It is an inhibitor of serine and cysteine proteases. It has been crystallised in complexes with

carboxypeptidase A carboxypeptidase ( EC number 3.4.16 - 3.4.18) is a protease enzyme that hydrolyzes (cleaves) a peptide bond at the carboxy-terminal (C-terminal) end of a protein or peptide. This is in contrast to an aminopeptidases, which cleave peptide bonds ...

, which is obtained from

wheat Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeological ...

, and ''

Leishmania major ''Leishmania major'' is a species of parasite found in the genus ''Leishmania'', and is associated with the disease zoonotic cutaneous leishmaniasis (also known as Aleppo boil, Baghdad boil, Bay sore, Biskra button, Chiclero ulcer, Delhi boil, K ...

oligopeptidase An Oligopeptidase is an enzyme that cleaves peptides but not proteins. This property is due to its structure: the active site of this enzyme is located at the end of a narrow cavity which can only be reached by peptides. History Background Prote ...

B. In both cases, the backbone carbonyl of the terminal

arginine Arginine is the amino acid with the formula (H2N)(HN)CN(H)(CH2)3CH(NH2)CO2H. The molecule features a guanidino group appended to a standard amino acid framework. At physiological pH, the carboxylic acid is deprotonated (−CO2−) and both the a ...

of antipain forms a covalent bond to the active site

serine Serine (symbol Ser or S) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated − form under biological conditions), a carboxyl group (which is in the deprotonated − form un ...

in the protease. In oncology, pain control is an ongoing problem. An important obstacle to controlling cancer pain is related to the patient. A recent research article indicated that antipain Y is a new type of anti-pain analog, which can inhibit the release of neurotransmitter in rat dorsal root ganglion neurons. An experiment focused on potential improvement for pain management of

oncology Oncology is a branch of medicine that deals with the study, treatment, diagnosis and prevention of cancer. A medical professional who practices oncology is an ''oncologist''. The name's etymological origin is the Greek word ὄγκος (''� ...

patients with antipain. A study was performed for information on the effect of antipain on the quality of post-thawed ram

semen Semen, also known as seminal fluid, is an organic bodily fluid created to contain spermatozoa. It is secreted by the gonads (sexual glands) and other sexual organs of male or hermaphroditic animals and can fertilize the female ovum. Semen is ...

. The results from this experiment concluded that antipain aided in the quality of ram semen by maintaining the sperm mobility. Antipain includes the function to inhibit a degrading enzyme, called

plasmin Plasmin is an important enzyme () present in blood that degrades many blood plasma proteins, including fibrin clots. The degradation of fibrin is termed fibrinolysis. In humans, the plasmin protein (in the zymogen form of plasminogen) is encode ...

, permitting this substance to be able to improve the resistance of membrane disruption by freezing temperatures.

Antiretroviral and protease inhibitors

There are several

serine proteases Serine proteases (or serine endopeptidases) are enzymes that cleave peptide bonds in proteins. Serine serves as the nucleophilic amino acid at the (enzyme's) active site. They are found ubiquitously in both eukaryotes and prokaryotes. Ser ...

, which are enzymes that cleave the protein bond, in the

human genome The human genome is a complete set of nucleic acid sequences for humans, encoded as DNA within the 23 chromosome pairs in cell nuclei and in a small DNA molecule found within individual Mitochondrial DNA, mitochondria. These are usually treated s ...

Proteases A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes (increases reaction rate or "speeds up") proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the form ...

are ubiquitous. Protease function is also affected by

endogenous Endogenous substances and processes are those that originate from within a living system such as an organism, tissue, or cell. In contrast, exogenous substances and processes are those that originate from outside of an organism. For example, es ...

inhibitors. The abnormal functioning of these proteases can lead to the development of cancerous tumors. Protease inhibitors or antipain are enzymes that are used to regulate their performance. The antiretroviral drug

Nelfinavir Nelfinavir, sold under the brand name Viracept, is an antiretroviral medication used in the treatment of HIV/AIDS. Nelfinavir belongs to the class of drugs known as protease inhibitors (PIs) and like other PIs is almost always used in combinatio ...

is one example of an antipain. It was classified as an antipain after a study published by

Ovid Pūblius Ovidius Nāsō (; 20 March 43 BC – 17/18 AD), known in English as Ovid ( ), was a Roman poet who lived during the reign of Augustus. He was a contemporary of the older Virgil and Horace, with whom he is often ranked as one of the t ...

that investigated the in vitro effect of

using proteolytic foot printing and found that it selectively inhibited HER2- positive, a growth factor in breast cancer. Antipain is a reversible inhibitor of trypsin, papain, and, plasmin, which is isolated from actinomycetes.

Protease inhibitors and DRUG neurons

Protease-activated receptors (PARs) are a unique class of

G protein-coupled receptor G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large group of evolutionarily-related p ...

s activated by proteolytic cleavage of the receptor N terminus. PARs are activated by some Serine Proteases and are important for the physiological, psychological, and pathological functions of the human body. During the study, an antipain analogue Y was developed and studied. It was shown to have properties as a protease inhibitors but it had a low

IC50 The half maximal inhibitory concentration (IC50) is a measure of the potency of a substance in inhibiting a specific biological or biochemical function. IC50 is a quantitative measure that indicates how much of a particular inhibitory substance ...

than a antipain. Antipain analogue Y was able to suppress

Trypsin Trypsin is an enzyme in the first section of the small intestine that starts the digestion of protein molecules by cutting these long chains of amino acids into smaller pieces. It is a serine protease from the PA clan superfamily, found in the di ...

, which inhibits the secretion of an excitatory neuropeptide that leads to inflammation and other disorders. Antipain is a protease inhibitor, usually 1–2 μg/mL, and is well-against to cathepsin A, cathepsin B, papain and trypsin protease enzymes.

References

Peptides Aldehydes {{biochem-stub