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Thiolase
Thiolases, also known as acetyl-coenzyme A acetyltransferases (ACAT), are enzymes which convert two units of acetyl-CoA to acetoacetyl CoA in the mevalonate pathway. Thiolases are ubiquitous enzymes that have key roles in many vital biochemical pathways, including the beta oxidation pathway of fatty acid degradation and various biosynthetic pathways. Members of the thiolase family can be divided into two broad categories: degradative thiolases (EC 2.3.1.16) and biosynthetic thiolases (EC 2.3.1.9). These two different types of thiolase are found both in eukaryotes and in prokaryotes: acetoacetyl-CoA thiolase (EC:2.3.1.9) and 3-ketoacyl-CoA thiolase (EC:2.3.1.16). 3-ketoacyl-CoA thiolase (also called thiolase I) has a broad chain-length specificity for its substrates and is involved in degradative pathways such as fatty acid beta-oxidation. Acetoacetyl-CoA thiolase (also called thiolase II) is specific for the thiolysis of acetoacetyl-CoA and involved in biosynthetic pathways s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3-oxoadipyl-CoA Thiolase
In enzymology, a 3-oxoadipyl-CoA thiolase () is an enzyme that catalyzes the chemical reaction :succinyl-CoA + acetyl-CoA \rightleftharpoons CoA + 3-oxoadipyl-CoA Thus, the two substrates of this enzyme are succinyl-CoA and acetyl-CoA, whereas its two products are CoA and 3-oxoadipyl-CoA. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is succinyl-CoA:acetyl-CoA C-succinyltransferase. This enzyme participates in benzoate degradation via hydroxylation. 3-Oxoadipyl-CoA thiolase belongs to the thiolase Thiolases, also known as acetyl-coenzyme A acetyltransferases (ACAT), are enzymes which convert two units of acetyl-CoA to acetoacetyl CoA in the mevalonate pathway. Thiolases are ubiquitous enzymes that have key roles in many vital biochemi ... family of enzymes. References * * EC 2.3.1 Enzymes of unknown structure {{2.3-enzyme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetoacetyl-CoA
Acetoacetyl CoA is the precursor of HMG-CoA in the mevalonate pathway, which is essential for cholesterol biosynthesis. It also takes a similar role in the ketone bodies synthesis (ketogenesis) pathway of the liver. In the ketone bodies digestion pathway (in the tissue), it is no longer associated with having HMG-CoA as a product or as a reactant. It is created from acetyl-CoA, a thioester, which reacts with the enolate of a second molecule of acetyl-CoA in a Claisen condensation reaction, and it is acted upon by HMG-CoA synthase to form HMG-CoA. During the metabolism of leucine, this last reaction is reversed. Some individuals may experience Acetoacetyl-CoA deficiency. This deficiency is classified as a disorder ketone body and isoleucine metabolism that can be inherited. Additional mutations include those with the enzymes within pathways related to Acetoacetyl CoA, including Beta-Ketothiolase deficiency and Mitochondrial 3-hydroxy-3-methylglutaryl-CoA Synthase mutation. Addit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetoacetyl CoA
Acetoacetyl CoA is the precursor of HMG-CoA in the mevalonate pathway, which is essential for cholesterol biosynthesis. It also takes a similar role in the ketone bodies synthesis (ketogenesis) pathway of the liver. In the ketone bodies digestion pathway (in the tissue), it is no longer associated with having HMG-CoA as a product or as a reactant. It is created from acetyl-CoA, a thioester, which reacts with the enolate of a second molecule of acetyl-CoA in a Claisen condensation reaction, and it is acted upon by HMG-CoA synthase to form HMG-CoA. During the metabolism of leucine, this last reaction is reversed. Some individuals may experience Acetoacetyl-CoA deficiency. This deficiency is classified as a disorder ketone body and isoleucine metabolism that can be inherited. Additional mutations include those with the enzymes within pathways related to Acetoacetyl CoA, including Beta-Ketothiolase deficiency and Mitochondrial 3-hydroxy-3-methylglutaryl-CoA Synthase mutation. Addit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta Oxidation
In biochemistry and metabolism, beta-oxidation is the catabolic process by which fatty acid molecules are broken down in the cytosol in prokaryotes and in the mitochondria in eukaryotes to generate acetyl-CoA, which enters the citric acid cycle, and NADH and FADH2, which are co-enzymes used in the electron transport chain. It is named as such because the beta carbon of the fatty acid undergoes oxidation to a carbonyl group. Beta-oxidation is primarily facilitated by the mitochondrial trifunctional protein, an enzyme complex associated with the inner mitochondrial membrane, although very long chain fatty acids are oxidized in peroxisomes. The overall reaction for one cycle of beta oxidation is: :C''n''-acyl-CoA + FAD + + + CoA → C''n''-2-acyl-CoA + + NADH + + acetyl-CoA Activation and membrane transport Free fatty acids cannot penetrate any biological membrane due to their negative charge. Free fatty acids must cross the cell membrane through specific transport pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetyl-CoA C-acetyltransferase
In enzymology, an acetyl-CoA C-acetyltransferase () is an enzyme that catalyzes the chemical reaction :2 acetyl-CoA \rightleftharpoons CoA + acetoacetyl-CoA Hence, this enzyme has one substrate, acetyl-CoA, and two products, CoA and acetoacetyl-CoA. Acetyl-CoA C-acetyltransferase belongs to the thiolase family of enzymes. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acetyl-CoA:acetyl-CoA C-acetyltransferase. Other names in common use include acetoacetyl-CoA thiolase, beta-acetoacetyl coenzyme A thiolase, 2-methylacetoacetyl-CoA thiolase isleading'', 3-oxothiolase, acetyl coenzyme A thiolase, acetyl-CoA acetyltransferase, acetyl-CoA:N-acetyltransferase, and thiolase II. This enzyme participates in 10 metabolic pathways: fatty acid metabolism, synthesis and degradation of ketone bodies, valine, leucine and isoleucine degradation, lysine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mevalonate Pathway
The mevalonate pathway, also known as the isoprenoid pathway or HMG-CoA reductase pathway is an essential metabolic pathway present in eukaryotes, archaea, and some bacteria. The pathway produces two five-carbon building blocks called isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP), which are used to make isoprenoids, a diverse class of over 30,000 biomolecules such as cholesterol, vitamin K, coenzyme Q10, and all steroid hormones. The mevalonate pathway begins with acetyl-CoA and ends with the production of IPP and DMAPP. It is best known as the target of statins, a class of cholesterol lowering drugs. Statins inhibit HMG-CoA reductase within the mevalonate pathway. Upper mevalonate pathway The mevalonate pathway of eukaryotes, archaea, and eubacteria all begin the same way. The sole carbon feed stock of the pathway is acetyl-CoA. The first step condenses two acetyl-CoA molecules to yield acetoacetyl-CoA. This is followed by a second condensation to for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ACAA1
3-Ketoacyl-CoA thiolase, peroxisomal also known as acetyl-Coenzyme A acyltransferase 1 is an enzyme that in humans is encoded by the ''ACAA1'' gene. Acetyl-Coenzyme A acyltransferase 1 is an acetyl-CoA C-acyltransferase enzyme. Function This gene encodes an enzyme operative in the beta oxidation system of the peroxisomes. Clinical significance Deficiency of this enzyme leads to pseudo-Zellweger syndrome Zellweger syndrome is a rare congenital disorder characterized by the reduction or absence of functional peroxisomes in the cells of an individual. It is one of a family of disorders called Zellweger spectrum disorders which are leukodystrophies .... References External links * Further reading * * * * * * * * * * * * * * * * Human proteins {{gene-3-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ACAA2
3-Ketoacyl-CoA thiolase, mitochondrial also known as acetyl-Coenzyme A acyltransferase 2 is an enzyme that in humans is encoded by the ''ACAA2'' gene. Acetyl-Coenzyme A acyltransferase 2 is an acetyl-CoA C-acyltransferase enzyme. Structure The ACAA2 gene encodes a 41.9 kDa protein that is composed of 397 amino acids and contains 88 observed peptides.] Function The encoded protein catalyzes the last step of the mitochondrion, mitochondrial fatty acid beta oxidation In biochemistry and metabolism, beta-oxidation is the catabolic process by which fatty acid molecules are broken down in the cytosol in prokaryotes and in the mitochondria in eukaryotes to generate acetyl-CoA, which enters the citric acid cycl ... spiral. Unlike most mitochondrial matrix proteins, it contains a non-cleavable amino-terminal targeting signal. ACAA2 has been shown to be a functional BNIP3 binding partner, which provides a possible link between fatty acid metabolism and cell apoptosis. Clinical s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HADHB
Trifunctional enzyme subunit beta, mitochondrial (TP-beta) also known as 3-ketoacyl-CoA thiolase, acetyl-CoA acyltransferase, or beta-ketothiolase is an enzyme that in humans is encoded by the ''HADHB'' gene. HADHB is a subunit of the mitochondrial trifunctional protein and has thiolase activity. Structure The HADHB gene is located on chromosome 2 (human), chromosome 2, with its specific location being 2p23. The gene contains 17 exons. HADHB encodes a 51.2 kDa protein that is composed of 474 amino acids; 124 peptides have been observed through mass spectrometry data.] Function This gene encodes the beta subunit of the mitochondrial trifunctional protein, a catalyst of mitochondrial beta-oxidation of long chain fatty acids. The HADHB protein catalyzes the final step of beta-oxidation, in which 3-ketoacyl CoA is cleaved by the thiol group of another molecule of Coenzyme A. The thiol is inserted between C-2 and C-3, which yields an acetyl CoA molecule and an acyl CoA molecule, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propionyl-CoA C2-trimethyltridecanoyltransferase
In enzymology, a propionyl-CoA C2-trimethyltridecanoyltransferase () is an enzyme that catalyzes the chemical reaction :4,8,12-trimethyltridecanoyl-CoA + propanoyl-CoA \rightleftharpoons 3-oxopristanoyl-CoA + CoA Thus, the two substrates of this enzyme are 4,8,12-trimethyltridecanoyl-CoA and propanoyl-CoA, whereas its two products are 3-oxopristanoyl-CoA and CoA. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivial ... of this enzyme class is 4,8,12-trimethyltridecanoyl-CoA:propanoyl-CoA C2-4,8,12-trimethyltridecanoyltransferase. Other names in common use include 3-oxopristanoyl-CoA hydrolase, 3-oxopristanoyl-CoA thiolase, per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SCP2
Non-specific lipid-transfer protein also known as sterol carrier protein 2 (SCP-2) or propanoyl-CoA C-acyltransferase is a protein that in humans is encoded by the ''SCP2'' gene. Function This gene encodes two proteins: sterol carrier protein X (SCPx) and sterol carrier protein 2 (SCP2), as a result of transcription initiation from 2 independently regulated promoters. The transcript initiated from the proximal promoter encodes the longer SCPx protein, and the transcript initiated from the distal promoter encodes the shorter SCP2 protein, with the 2 proteins sharing a common C-terminus. Evidence suggests that the SCPx protein is a peroxisome-associated thiolase that is involved in the oxidation of branched chain fatty acids, while the SCP2 protein is thought to be an intracellular lipid transfer protein. Alternative splicing of this gene produces multiple transcript variants, some encoding different isoforms. The full-length nature of all transcript variants has not been determi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propanoyl-CoA C-acyltransferase
In enzymology, a propanoyl-CoA C-acyltransferase () is an enzyme that catalyzes the chemical reaction :3alpha,7alpha,12alpha-trihydroxy-5beta-cholanoyl-CoA + propanoyl-CoA \rightleftharpoons CoA + 3alpha,7alpha,12alpha-trihydroxy-24-oxo-5beta-cholestanoyl-CoA Thus, the two substrates of this enzyme are 3alpha,7alpha,12alpha-trihydroxy-5beta-cholanoyl-CoA and propanoyl-CoA, whereas its two products are CoA and 3alpha,7alpha,12alpha-trihydroxy-24-oxo-5beta-cholestanoyl-CoA. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is 3alpha,7alpha,12alpha-trihydroxy-5beta-cholanoyl-CoA:propanoyl-CoA C-acyltransferase. Other names in common use include peroxisomal thiolase 2, sterol carrier protein-, SCP, and PTE-2 (ambiguous). This enzyme participates in ppar signaling pathway. Propanoyl-CoA C-acyltransferase belongs to the thiolase Thiolases, also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
