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esterase is a
hydrolaseIn biochemistry, a hydrolase is an enzyme that catalyzes the hydrolysis of a chemical bond. For example, an enzyme that catalyzed the following reaction is a hydrolase:-Nomenclature:...
enzymeEnzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that splits
esterEsters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...
s into an
acidAn acid is a substance which reacts with a base. Commonly, acids can be identified as tasting sour, reacting with metals such as calcium, and bases like sodium carbonate. Aqueous acids have a pH of less than 7, where an acid of lower pH is typically stronger, and turn blue litmus paper red...
and an
alcoholIn chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....
in a
chemical reactionA chemical reaction is a process that leads to the transformation of one set of chemical substances to another. Chemical reactions can be either spontaneous, requiring no input of energy, or non-spontaneous, typically following the input of some type of energy, such as heat, light or electricity...
with water called
hydrolysisHydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...
.
A wide range of different esterases exist that differ in their
substrateIn biochemistry, a substrate is a molecule upon which an enzyme acts. Enzymes catalyze chemical reactions involving the substrate. In the case of a single substrate, the substrate binds with the enzyme active site, and an enzyme-substrate complex is formed. The substrate is transformed into one or...
specificity, their
protein structureProteins are an important class of biological macromolecules present in all organisms. Proteins are polymers of amino acids. Classified by their physical size, proteins are nanoparticles . Each protein polymer – also known as a polypeptide – consists of a sequence formed from 20 possible L-α-amino...
, and their biological function.
EC classification/list of enzymes
-
- Acetylesterase
In enzymology, an acetylesterase is an enzyme that catalyzes the chemical reactionThus, the two substrates of this enzyme are acetic ester and H2O, whereas its two products are alcohol and acetate....
(EC 3.1.1.6), splits off acetylIn organic chemistry, acetyl is a functional group, the acyl with chemical formula COCH3. It is sometimes represented by the symbol Ac . The acetyl group contains a methyl group single-bonded to a carbonyl...
groupsIn organic chemistry, functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. The same functional group will undergo the same or similar chemical reaction regardless of the size of the molecule it is a part of...
- Cholinesterase
In biochemistry, cholinesterase is a family of enzymes that catalyze the hydrolysis of the neurotransmitter acetylcholine into choline and acetic acid, a reaction necessary to allow a cholinergic neuron to return to its resting state after activation.-Types:...
- Acetylcholinesterase
"Acetylcholinesterase, also known as AChE or acetylcholine acetylhydrolase, is an enzyme that degrades the neurotransmitter acetylcholine, producing choline and an acetate group. It is mainly found at neuromuscular junctions and cholinergic nervous system, where its activity serves to terminate...
, inactivates the neurotransmitterNeurotransmitters are endogenous chemicals that transmit signals from a neuron to a target cell across a synapse. Neurotransmitters are packaged into synaptic vesicles clustered beneath the membrane on the presynaptic side of a synapse, and are released into the synaptic cleft, where they bind to...
acetylcholineThe chemical compound acetylcholine is a neurotransmitter in both the peripheral nervous system and central nervous system in many organisms including humans...
- Pseudocholinesterase, broad substrate specificity, found in the blood plasma
Blood plasma is the straw-colored liquid component of blood in which the blood cells in whole blood are normally suspended. It makes up about 55% of the total blood volume. It is the intravascular fluid part of extracellular fluid...
and in the liverThe liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...
- Pectinesterase
Pectinesterase is a ubiquitous cell-wall-associated enzyme that presents several isoforms that facilitate plant cell wall modification and subsequent breakdown. It is found in all higher plants as well as in some bacteria and fungi...
(EC 3.1.1.11), clarifies fruit juices
- EC 3.1.2: Thiolester hydrolases
- Thioesterase
Thioesterases are enzymes which belong to the Esterase family. Esterases, in turn, are one type of the several hydrolases known.Thioesterases exhibit Esterase activity specifically at a thiol group.Thioesterases or thiolester hydrolases are identified as members of E.C.3.1.2.-Examples:Acetyl-coA...
- Ubiquitin carboxy-terminal hydrolase L1
Ubiquitin carboxy-terminal hydrolase L1 is a deubiqutinating enzyme.-Pathology:A point mutation in the gene encoding this protein is implicated as the cause of Parkinson's disease in one kindred....
- EC 3.1.3: Phosphoric monoester hydrolases
Phosphoric monoester hydrolases are enzymes that catalyse the hydrolysis of O-P bonds by nucleophillic attack of phosphorus by cysteine residues or coordinated metal ions.They are categorized with the EC number 3.1.3....
- Phosphatase
A phosphatase is an enzyme that removes a phosphate group from its substrate by hydrolysing phosphoric acid monoesters into a phosphate ion and a molecule with a free hydroxyl group . This action is directly opposite to that of phosphorylases and kinases, which attach phosphate groups to their...
(EC 3.1.3.x), hydrolyses phosphoric acid monoesters into a phosphateA phosphate, an inorganic chemical, is a salt of phosphoric acid. In organic chemistry, a phosphate, or organophosphate, is an ester of phosphoric acid. Organic phosphates are important in biochemistry and biogeochemistry or ecology. Inorganic phosphates are mined to obtain phosphorus for use in...
ion and an alcohol
- Alkaline phosphatase
Alkaline phosphatase is a hydrolase enzyme responsible for removing phosphate groups from many types of molecules, including nucleotides, proteins, and alkaloids. The process of removing the phosphate group is called dephosphorylation...
, removes phosphate groups from many types of molecules, including nucleotides, proteins, and alkaloids.
- Phosphodiesterase
A phosphodiesterase is any enzyme that breaks a phosphodiester bond. Usually, people speaking of phosphodiesterase are referring to cyclic nucleotide phosphodiesterases, which have great clinical significance and are described below...
(PDE), inactivates the second messenger cAMPCyclic adenosine monophosphate is a second messenger important in many biological processes...
- cGMP specific phosphodiesterase type 5
cGMP-specific phosphodiesterase type 5 is an enzyme from the phosphodiesterase class. It is found in various tissues, most prominently the corpus cavernosum and the retina....
, is inhibited by SildenafilSildenafil citrate, sold as Viagra, Revatio and under various other trade names, is a drug used to treat erectile dysfunction and pulmonary arterial hypertension . It was originally developed by British scientists and then brought to market by the US-based pharmaceutical company Pfizer...
(Viagra)
- Fructose bisphosphatase
Fructose bisphosphatase is an enzyme in the liver that converts fructose-1,6-bisphosphate to fructose 6-phosphate in gluconeogenesis . Fructose bisphosphatase catalyses the reverse of the reaction which is catalysed by phosphofructokinase, which is involved in the process of glycolysis...
(3.1.3.11), converts fructose-1,6-bisphosphate to fructose-6-phosphate in gluconeogenesisGluconeogenesis is a metabolic pathway that results in the generation of glucose from non-carbohydrate carbon substrates such as lactate, glycerol, and glucogenic amino acids....
- EC 3.1.4: Phosphoric diester hydrolases
- EC 3.1.5: Triphosphoric monoester hydrolases
- EC 3.1.6: Sulfuric ester hydrolases (sulfatases)
- EC 3.1.7: Diphosphoric monoester hydrolases
- EC 3.1.8: Phosphoric triester hydrolases
- Exonuclease
Exonucleases are enzymes that work by cleaving nucleotides one at a time from the end of a polynucleotide chain. A hydrolyzing reaction that breaks phosphodiester bonds at either the 3’ or the 5’ end occurs. Its close relative is the endonuclease, which cleaves phosphodiester bonds in the middle ...
s (deoxyribonucleaseA deoxyribonuclease is any enzyme that catalyzes the hydrolytic cleavage of phosphodiester linkages in the DNA backbone. Thus, deoxyribonucleases are one type of nuclease...
s and ribonucleaseRibonuclease is a type of nuclease that catalyzes the degradation of RNA into smaller components. Ribonucleases can be divided into endoribonucleases and exoribonucleases, and comprise several sub-classes within the EC 2.7 and 3.1 classes of enzymes.-Function:All organisms studied contain...
s)
- EC 3.1.11: Exodeoxyribonucleases
Exodeoxyribonucleases are enzymes are in the EC number family 3.1.11.They catalyze the division of DNA.They are a type of esterase....
producing 5'-phosphomonoesters
- EC 3.1.13: Exoribonucleases producing 5'-phosphomonoesters
- EC 3.1.14: Exoribonucleases producing 3'-phosphomonoesters
- EC 3.1.15: Exonucleases active with either ribo- or deoxy-
- Endonuclease
Endonucleases are enzymes that cleave the phosphodiester bond within a polynucleotide chain, in contrast to exonucleases, which cleave phosphodiester bonds at the end of a polynucleotide chain. Typically, a restriction site will be a palindromic sequence four to six nucleotides long. Most...
s (deoxyribonucleaseA deoxyribonuclease is any enzyme that catalyzes the hydrolytic cleavage of phosphodiester linkages in the DNA backbone. Thus, deoxyribonucleases are one type of nuclease...
s and ribonucleaseRibonuclease is a type of nuclease that catalyzes the degradation of RNA into smaller components. Ribonucleases can be divided into endoribonucleases and exoribonucleases, and comprise several sub-classes within the EC 2.7 and 3.1 classes of enzymes.-Function:All organisms studied contain...
s)
- Endodeoxyribonuclease
Endodeoxyribonuclease is a endonuclease ribonuclease.Restriction enzymes are a type of endodeoxyribonuclease.More examples: Deoxyribonuclease I, Deoxyribonuclease II, Deoxyribonuclease IV, UvrABC endonuclease...
- Endoribonuclease
A Endoribonuclease is a ribonuclease endonuclease. It cleaves either single-stranded or double-stranded RNA, depending on the enzyme. Example includes both single proteins like RNase III, RNase A, RNase T1, and RNase H, and also complexes of proteins like RNase P and the RNA-induced silencing...
- either deoxy- or ribo-
See also
- Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
- List of enzymes
- Carboxylic acid
Carboxylic acids are organic acids characterized by the presence of at least one carboxyl group. The general formula of a carboxylic acid is R-COOH, where R is some monovalent functional group...
- Ester
Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...
- Leukocyte esterase
Leukocyte esterase is a urine test for the presence of white blood cells and other abnormalities associated with infection.White blood cells in the urine usually indicate a urinary tract infection. The leukocyte esterase test detects esterase, an enzyme released by white blood cells. Positive...
- Hemagglutinin esterase
- Nuclease
A nuclease is an enzyme capable of cleaving the phosphodiester bonds between the nucleotide subunits of nucleic acids. Older publications may use terms such as "polynucleotidase" or "nucleodepolymerase"....
- Lipase
A lipase is an enzyme that catalyzes the formation or cleavage of fats . Lipases are a subclass of the esterases.Lipases perform essential roles in the digestion, transport and processing of dietary lipids in most, if not all, living organisms...
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