Enzymes

thumb|400px|The enzyme glucosidase converts the sugar [[maltose into two glucose sugars. Active site residues in red, maltose substrate in black, and NAD cofactor in yellow. ()|alt=Ribbon diagram of glycosidase with an arrow showing the cleavage of the maltose sugar substrate into two glucose products.]]

An amylase () is an enzyme that catalyses the hydrolysis of starch (Latin '''') into sugars. Amylase is present in the saliva of humans and some other mammals, where it begins the chemical process of digestion. Foods that contain large amounts of starch but little sugar, such as rice and potatoes, may acquire a slightly sweet taste as they are chewed because amylase degrades some of their starch into sugar. The pancreas and salivary gland make amylase (alpha amylase) to hydrolyse dietary starch into disaccharides and trisaccharides which are converted by other enzymes to glucose to supply the

Enzyme that synthesizes DNA from a nucleic acid template

Catalase is a common enzyme found in nearly all living organisms exposed to oxygen (such as bacteria, plants, and animals) which catalyzes the decomposition of hydrogen peroxide to water and oxygen. It is a very important enzyme in protecting the cell from oxidative damage by reactive oxygen species (ROS). Catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert millions of hydrogen peroxide molecules to water and oxygen each second.

complex that catalyzes the phosphorylation of ADP to ATP, during oxidative phosphorylation

class of enzymes that synthesize RNA from a DNA template

a chemical compound or metallic ion that is required for a protein's biological activity to happen

active site of an enzyme; region of an enzyme where substrate molecules bind and undergo a chemical reaction to form products

In biochemistry, isozymes (also known as isoenzymes or more generally as multiple forms of enzymes or isoforms) are enzymes that differ in amino acid sequence but catalyze the same chemical reaction. Isozymes usually have different kinetic parameters (e.g. different KM values), or are regulated differently. They permit the fine-tuning of metabolism to meet the particular needs of a given tissue or developmental stage.

In biochemistry, a zymogen (), also called a proenzyme (), is an inactive precursor of an enzyme. A zymogen requires a biochemical change (such as a hydrolysis reaction revealing the active site, or changing the configuration to reveal the active site) to become an active enzyme. The biochemical change usually occurs in Golgi bodies, where a specific part of the precursor enzyme is cleaved in order to activate it. The inactivating piece which is cleaved off can be a peptide unit, or can be independently-folding domains comprising more than 100 residues. Although they limit the enzyme's ability

mammalian protein found in Homo sapiens

class of enzymes

thumb|Ribbon diagram representation of Taq DNA polymerase

400px|thumb|right|Ribbon representation of the Streptomyces lividans β-1,4-endoglucanase catalytic domain - an example from the family 12 glycoside hydrolases

α-Amylase is an enzyme (; systematic name 4-α-D-glucan glucanohydrolase) that hydrolyses α bonds of large, α-linked polysaccharides, such as starch and glycogen, yielding shorter chains thereof, dextrins, and maltose, through the following biochemical process:

catalysis of chemical reactions by specialized proteins known as enzymes

Retroviral integrase (IN) is an enzyme produced by a retrovirus (such as HIV) that integrates (forms covalent links between) its genetic information into that of the host cell it infects. Retroviral INs are not to be confused with phage integrases (recombinases) used in biotechnology, such as λ phage integrase, as discussed in site-specific recombination.

class of enzymes

class of enzymes

Lipoxygenases () (LOX) are a family of (non-heme) iron-containing enzymes, more specifically oxidative enzymes, most of which catalyze the dioxygenation of polyunsaturated fatty acids in lipids containing a cis,cis-1,4-pentadiene into cell signaling agents that serve diverse roles as autocrine signals that regulate the function of their parent cells, paracrine signals that regulate the function of nearby cells, and endocrine signals that regulate the function of distant cells.

thumb|right|220px|Carboxypeptidase A, from bovine pancreas 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 at the N-terminus of proteins. Humans, animals, bacteria and plants contain several types of carboxypeptidases that have diverse functions ranging from catabolism to protein maturation. At least two mechanisms have been discussed.

Butyrylcholinesterase (HGNC symbol BCHE; EC 3.1.1.8), also known as BChE, BuChE, BuChase, pseudocholinesterase, or plasma (cholin)esterase, is a nonspecific cholinesterase, an enzyme that hydrolyses many different choline-based esters. In humans, it is made in the liver, found mainly in blood plasma, and encoded by the BCHE gene.

Zymase (also known as alcoholase) is an obsolete term for an enzyme complex that catalyzes the fermentation of sugar into ethanol and carbon dioxide. It occurs naturally in yeasts. Zymase activity varies among yeast strains.

Sirtuins are a family of signaling proteins involved in metabolic regulation. They are ancient in animal evolution and appear to possess a highly conserved structure throughout all kingdoms of life. Chemically, sirtuins are a class of proteins that possess either mono-ADP-ribosyltransferase or deacylase activity, including deacetylase, desuccinylase, demalonylase, demyristoylase and depalmitoylase activity. The name Sir2 comes from the yeast gene 'silent mating-type information regulation 2', the gene responsible for cellular regulation in yeast.

Chitinases (, chitodextrinase, 1,4-β-poly-N-acetylglucosaminidase, poly-β-glucosaminidase, β-1,4-poly-N-acetyl glucosamidinase, poly[1,4-(N-acetyl-β-D-glucosaminide)] glycanohydrolase, (1→4)-2-acetamido-2-deoxy-β-D-glucan glycanohydrolase; systematic name (1→4)-2-acetamido-2-deoxy-β-D-glucan glycanohydrolase) are hydrolytic enzymes that break down glycosidic bonds in chitin. They catalyse the following reaction:

mammalian protein found in Homo sapiens

An abzyme (from antibody and enzyme), also called catmab (from catalytic monoclonal antibody), and most often called catalytic antibody or sometimes catab, is a monoclonal antibody with catalytic activity. Abzymes are usually raised in lab animals immunized against synthetic haptens, but some natural abzymes can be found in normal humans (anti-vasoactive intestinal peptide autoantibodies) and in patients with autoimmune diseases such as systemic lupus erythematosus, where they can bind to and hydrolyze DNA. To date abzymes display only weak, modest catalytic activity and have not proved to be

An exopeptidase is any peptidase that catalyzes the cleavage of the terminal (or the penultimate) peptide bond; the process releases a single amino acid, dipeptide or a tripeptide from the peptide chain. Depending on whether the amino acid is released from the amino or the carboxy terminal (N-terminus or C-terminus), an exopeptidase is further classified as an aminopeptidase or a carboxypeptidase, respectively. Thus, an aminopeptidase, an enzyme in the brush border of the small intestine, will cleave a single amino acid from the amino terminal, whereas carboxypeptidase, which is a digestive en

class of enzymes

thumb|Molecular structure of tryptophan 2,3-dioxygenase An oxygenase is any enzyme that oxidizes a substrate by transferring the oxygen from molecular oxygen O2 (as in air) to it. The oxygenases form a class of oxidoreductases; their EC number is EC 1.13 or EC 1.14.

β-Galactosidase (EC 3.2.1.23, beta-gal or β-gal; systematic name β-D-galactoside galactohydrolase) is a glycoside hydrolase enzyme that catalyzes hydrolysis of terminal non-reducing β-D-galactose residues in β-D-galactosides. (This enzyme digests many β-Galactosides, not just lactose. It is sometimes loosely referred to as lactase but that name is generally reserved for mammalian digestive enzymes that break down lactose specifically.)

biochemical and genetic engineering processes involved in the synthesis, modification, and production of protein products for various applications

Steroid 21-hydroxylase is a protein that in humans is encoded by the CYP21A2 gene. The protein is an enzyme that hydroxylates steroids at the C21 position on the molecule. Naming conventions for enzymes are based on the substrate acted upon and the chemical process performed. Biochemically, this enzyme is involved in the biosynthesis of the adrenal gland hormones aldosterone and cortisol, which are important in blood pressure regulation, sodium homeostasis and blood sugar control. The enzyme converts progesterone and 17α-hydroxyprogesterone into 11-deoxycorticosterone and 11-deoxycortisol, res

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

pharmaceutical drug

pocket in the active site of an enzyme

complex that contains 10 different types of subunits

Integrons are genetic mechanisms that allow bacteria to adapt and evolve rapidly through the stockpiling and expression of new genes. These genes are embedded in a specific genetic structure called gene cassette (a term that is lately changing to integron cassette) that generally carries one promoterless open reading frame (ORF) together with a recombination site (attC). Integron cassettes are incorporated to the attI site of the integron platform by site-specific recombination reactions mediated by the integrase.

Alloenzymes (or also called allozymes) are variant forms of an enzyme which differ structurally but not functionally from other allozymes coded for by different alleles at the same locus. These are opposed to isozymes, which are enzymes that perform the same function, but which are coded by genes located at different loci.

class of enzymes

thumb|Three dimensional structure of an enzyme. Biocatalysis utilizes these biological macromolecules to catalyze small molecule transformations. Biocatalysis refers to the use of living (biological) systems or their parts to speed up (catalyze) chemical reactions. In biocatalytic processes, natural catalysts, such as enzymes, perform chemical transformations on organic compounds. Both enzymes that have been more or less isolated and enzymes still residing inside living cells are employed for this task. Modern biotechnology, specifically directed evolution, has made the production of modified

mammalian protein found in Homo sapiens

enzyme complex of which the core is a heterodimer composed of a light (alpha) and heavy (beta) chain, and requires several other water-soluble proteins of cytosolic origin for activity

family of enzymes

class of enzymes

Enzymes that can change shape when bound to by other proteins, altering their activity

laboratory method for measuring enzymatic activity

Wikimedia list article

Colipase, abbreviated CLPS, is a protein co-enzyme that counteracts the inhibitory effect of intestinal bile acid on the enzymatic activity of pancreatic lipase. It is secreted by the pancreas in an inactive form, procolipase, which is activated in the intestinal lumen by trypsin.

mammalian protein found in Homo sapiens

α-Galactosidase ( EC 3.2.1.22, α-GAL, α-GAL A; systematic name α-D-galactoside galactohydrolase) is a glycoside hydrolase enzyme that catalyses the following reaction:

class of enzymes

mammalian protein found in Homo sapiens

compound that increases the activity of a protein

mammalian protein found in Homo sapiens

Glycosylases (EC 3.2) are enzymes that hydrolyze glycosyl compounds. They are a type of hydrolase (EC 3). In turn, glycosylases are divided into two groups: glycosidases—enzymes that hydrolyze O- and S-glycosyl compounds (EC 3.2.1) -- and enzymes that hydrolyze N-glycosyl compounds (EC 3.2.2).

mammalian protein found in Homo sapiens

Deiodinase (monodeiodinase) is a peroxidase enzyme that is involved in the activation or deactivation of thyroid hormones.

class of enzymes