NationMaster - Encyclopedia: Proteolysis

Proteolysis is the directed degradation (digestion) of proteins by cellular enzymes called proteases or by intramolecular digestion. A representation of the 3D structure of myoglobin showing coloured alpha helices. ... Human glyoxalase I. Two zinc ions that are needed for the enzyme to catalyze its reaction are shown as purple spheres, and an enzyme inhibitor called S-hexylglutathione is shown as a space-filling model, filling the two active sites. ... Proteases (proteinases, peptidases, or proteolytic enzymes) are enzymes that break peptide bonds between amino acids of proteins. ...

Purposes

Proteolysis is also used in research and diagnostic applications: The N-terminal end refers to the extremity of a protein or polypeptide terminated by an amino acid with a free amine group (NH2). ... Methionine is an Î±-amino acid with the chemical formula HO2CCH(NH2)CH2CH2SCH3. ... Translation is the second stage of protein biosynthesis (part of the overall process of gene expression). ... A signal peptide is a short (15-60 amino acids long) peptide chain that directs the post transrational transport of a protein. ... The cell membrane (also called the plasma membrane, plasmalemma or phospholipid bilayer) is a selectively permeable lipid bilayer found in all cells. ... A common alternate meaning of virus is computer virus. ... Messenger RNA (mRNA) is said to be polycistronic when it contains the genetic information to translate more than one protein. ... This article is about the class of chemicals. ... A proenzyme is the inactive precursor to an active enzyme. ... A zymogen (or proenzyme) is an inactive enzyme precursor. ... A prehormone is a biochemical substance secreted by glandular tissue and has minimal or no significant biological activity, but it is converted in peripheral tissues into an active hormone. ... Cyclins are a family of proteins involved in the progression of cells through the cell cycle. ... The cell cycle, or cell-division cycle, is the series of events that take place in a eukaryotic cell leading to its replication. ...

A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... Gel electrophoresis is a technique used for the separation of deoxyribonucleic acid, ribonucleic acid, or protein molecules using an electric current applied to a gel matrix. ... Mass spectrometry (previously called mass spectroscopy (deprecated) or informally, mass-spec and MS) is an analytical technique that measures the mass-to-charge ratio of ions. ... For the journal Proteomics, see Proteomics (journal). ...

Examples

Trypsin (EC 3. ... Chymotrypsin (bovine Î³ chymotrypsin: PDB 1AB9, EC 3. ... Protein Crystal Growth Porcine Elastase In molecular biology, elastase is an enzyme from the class of proteases (or better peptidases) that break down proteins. ...

Venoms

Certain venoms, such as those produced by venomous snakes, can also cause proteolysis. These venoms are, in fact, highly-evolved digestive fluids that begin their work outside of the body. Proteolytic venoms cause a wide range of toxic effects^[1], including effects that are: For other uses, see Snake (disambiguation). ...

As citotoxinas sao umas cenas que matam as células. ... Hemotoxins, haemotoxins or hematotoxins are toxins that destroy red blood cells (that is, cause hemolysis), disrupt blood clotting, and/or cause organ degeneration and generalized tissue damage. ... Myotoxins are small, basic peptides found in snake venoms, such as in that of certain rattlesnakes. ... To meet Wikipedias quality standards, this article or section may require cleanup. ...

See also

A proteasome is a barrel-shaped multi-protein complex that can digest other proteins into short polypeptides and amino acids in an ATP-driven reaction. ...

References

External links

eMedicine is an online clinical medical knowledge base that was founded in 1996. ... A protein primary structure is a chain of amino acids. ... Posttranslational modification is the chemical modification of a protein after its translation. ... Protein biosynthesis (synthesis) is the process in which cells build proteins. ... A peptide bond is a chemical bond that is formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water (H2O). ... In chemistry racemization refers to partial conversion of one enantiomer into another. ... The N-terminal end refers to the extremity of a protein or polypeptide terminated by an amino acid with a free amine group (NH2). ... Acetylation describes a reaction, usually with acetic acid, that introduces an acetyl functional group into an organic compound. ... Categories: | | ... Pyroglutamic acid is an uncommon amino acid found in bacteriorhodopsin. ... Methylation is a term used in the chemical sciences to denote the attachment or substitution of a methyl group on various substrates. ... Glycation is the result of a sugar-reducing molecule, such as fructose or glucose, bonding to a protein or lipid molecule without the controlling action of an enzyme. ... This article needs to be wikified. ... The C-terminal end refers to the extremity of a protein or polypeptide terminated by an amino acid with a free carboxyl group (COOH). ... Amide functional group In chemistry, an amide is one of two kinds of compounds: the organic functional group characterized by a carbonyl group (C=O) linked to a nitrogen atom (N), or a compound that contains this functional group (pictured to the right); or a particular kind of nitrogen anion. ... A GPI anchor or glycosylphosphatidylinositol is a common posttranslational modification of the C-terminus of membrane-attached proteins. ... // Background Ubiquitylation, also termed ubiquitination, refers to the process particular to eukaryotes whereby a protein is post-translationally modified by covalent attachment of a small protein. ... Small Ubiquitin-related Modifier or SUMO proteins are a family of small proteins that are covalently attached to and detached from other proteins in cells to modify their function. ... Lysine is one of the 20 amino acids normally found in proteins. ... Methylation is a term used in the chemical sciences to denote the attachment or substitution of a methyl group on various substrates. ... Acetylation describes a reaction, usually with acetic acid, that introduces an acetyl functional group into an organic compound. ... In chemistry, acylation is the process of adding an acyl group to a compound. ... Hydroxylation is any chemical process that introduces one or more hydroxyl groups (-OH) into a compound (or radical) thereby oxidising it. ... Ubiquitin is a very conserved small regulatory protein that is ubiquitous in eukaryotes. ... Small Ubiquitin-related Modifier or SUMO proteins are a family of small proteins that are covalently attached to and detached from other proteins in cells to modify their function. ... A desmosine cross-link is formed when three allysyl side chains plus one unaltered lysl side chain from the same or neighbouring polypeptides. ... ADP ribose ADP-ribosylation is a posttranslational modification of proteins that involves the addition of one or more ADP and ribose moieties. ... Deamination is the removal of an amine group from a molecule. ... Oxidative deamination is a form of deamination which generates oxoacids in the liver. ... Cysteine is a naturally occurring, sulfur-containing amino acid that is found in most proteins, although only in small quantities. ... In chemistry, a disulfide bond is a single covalent bond derived from the coupling of thiol groups. ... Prenylation or isoprenylation is the addition of hydrophobic molecules to a protein to facilitate its attachment to the cell membrane. ... Palmitoylation is the covalent attachment of fatty acids to cysteine residues of membrane proteins [1] ^ Linder, M.E. (2000). ... Serine (IPA ), organic compound, one of the 20 amino acids commonly found in animal proteins. ... Threonine is one of the 20 natural amino acids. ... A phosphorylated serine residue Phosphorylation is the addition of a phosphate (PO4) group to a protein molecule or a small molecule. ... Glycosylation is the process or result of addition of saccharides to proteins and lipids. ... Histidine ammonia-lyase (or histidase) is an enzyme which converts histidine into ammonia and urocanic acid. ... Tyrosine (from the Greek tyros, meaning cheese, as it was first discovered in 1846 by German chemist Justus von Liebig in the protein casein from cheese[1][2]), 4-hydroxyphenylalanine, or 2-amino-3(4-hydroxyphenyl)-propanoic acid, is one of the 20 amino acids that are used by cells... A phosphorylated serine residue Phosphorylation is the addition of a phosphate (PO4) group to a protein molecule or a small molecule. ... Tyrosine sulfation is a posttranslational modification where a sulfate group is added to a tyrosine residue of a protein molecule. ... Structure of porphine, the simplest porphyrin. ... Riboflavin Flavin is a vaginal ring whose biochemical smell is pungent. ... It has been suggested that mGFP be merged into this article or section. ... For other articles using the abbreviation or acronym asn see ASN. Asparagine is one of the 20 most common natural amino acids on Earth. ... Deamidation reaction of Asn-Gly (top right) to Asp-Gly (at left) or iso(Asp)-Gly (in green at bottom right). ... Glycosylation is the process or result of addition of saccharides to proteins and lipids. ... Aspartic acid, also known as aspartate, the name of its anion, is one of the 20 natural proteinogenic amino acids which are the building blocks of proteins. ... Deamidation reaction of Asn-Gly (top right) to Asp-Gly (at left) or iso(Asp)-Gly (in green at bottom right). ... Glutamine (abbreviated as Gln or Q; Glx or Z represents either glutamine or glutamic acid) is one of the 20 amino acids encoded by the standard genetic code. ... Glutamate is the anion of glutamic acid. ... A carboxyl or carboxylic group is a functional group consisting of a carbon atom doubly bonded to an oxygen atom and single-bonded to a hydroxyl (-OH) group. ... Methylation is a term used in the chemical sciences to denote the attachment or substitution of a methyl group on various substrates. ... A form of reversible posttranslational modification of glutamate residues seen for example in alpha and beta tubulins, nucleosome assembly proteins NAP1 and NAP2. ... Polyglycylation is a form of posttranslational modification of glutamate residues of the carboxyl-terminal region tubulin in certain microtubules (eg axonemal) originally discovered in paramecium[1], and later shown in mammalian neurons as well[2]. ^ Redeker, V., Levilliers, N., Schmitter, J.M., Le Caer, J.P., Rossier, J., Adoutte, A... Arginine (abbreviated as Arg or R)[1] is an Î±-amino acid. ... Citrullination or deimination is the term used for the post-translational modification of the amino acid arginine in a protein into the amino acid citrulline. ... Methylation is a term used in the chemical sciences to denote the attachment or substitution of a methyl group on various substrates. ... Proline is an Î±-amino acid with the chemical formula HO2CCH(NH[CH2)3]. L-Proline is one of the twenty DNA-encoded amino acids. ... Hydroxylation is any chemical process that introduces one or more hydroxyl groups (-OH) into a compound (or radical) thereby oxidising it. ... In chemistry, an amino acid is any molecule that contains both amino and carboxylic acid functional groups. ... A representation of the 3D structure of the myoglobin protein. ...

Encyclopedia > Proteolysis

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