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Biotin Carboxyl Carrier Protein
Biotin Carboxyl Carrier Protein (BCCP) refers to proteins containing a biotin attachment domain that carry biotin and carboxybiotin throughout the ATP-dependent carboxylation by biotin-dependent carboxylases. In the case of '' E. coli'' Acetyl-CoA carboxylase, the BCCP is a separate protein known as ''accB'' (). On the other hand, in '' Haloferax mediterranei'' Propionyl-CoA carboxylase, the BCCP ''pccA'' () is fused with biotin carboxylase In enzymology, a biotin carboxylase () is an enzyme that Catalysis, catalyzes the chemical reaction : ATP + biotin-carboxyl-carrier protein + CO2 \rightleftharpoons ADP + phosphate + carboxybiotin-carboxyl-carrier protein The three Substrate .... Coenzymes Enzymes Metabolism Proteins {{Protein-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biotin Attachment Domain
Biotin/lipoyl attachment domain has a conserved lysine residue that binds biotin or lipoic acid. Biotin plays a catalytic role in some carboxyl transfer reactions and is covalently attached, via an amide bond, to a lysine residue in enzymes requiring this coenzyme. Lipoamide acyltransferases have an essential cofactor, lipoic acid, which is covalently bound via an amide linkage to a lysine group. The lipoic acid cofactor is found in a variety of proteins. Human proteins containing this domain ACACA; ACACB Acetyl-CoA carboxylase 2 also known as ACC-beta or ACC2 is an enzyme that in humans is encoded by the ''ACACB'' gene. Function Acetyl-CoA carboxylase (ACC) is a complex multifunctional enzyme system. ACC is a biotin-containing enzyme which cat ...; DBT; DLAT; DLST; DLSTP; MCCC1; PC; PCCA; PDHX; References {{DEFAULTSORT:Biotin Attachment Domain Protein domains ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biotin
Biotin (or vitamin B7) is one of the B vitamins. It is involved in a wide range of metabolic processes, both in humans and in other organisms, primarily related to the utilization of fats, carbohydrates, and amino acids. The name ''biotin'', borrowed from the German , derives from the Ancient Greek word (; 'life') and the suffix "-in" (a suffix used in chemistry usually to indicate 'forming'). Chemical description Biotin is classified as a heterocyclic compound, with a sulfur-containing ring fused ureido and tetrahydrothiophene group. A C5-carboxylic acid side chain is appended to one of the rings. The ureido ring, containing the −N−CO−N− group, serves as the carbon dioxide carrier in carboxylation reactions. Biotin is a coenzyme for five carboxylase enzymes, which are involved in the catabolism of amino acids and fatty acids, synthesis of fatty acids, and gluconeogenesis. Biotinylation of histone proteins in nuclear chromatin plays a role in chromatin stability and g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenosine Triphosphate
Adenosine triphosphate (ATP) is an organic compound that provides energy to drive many processes in living cells, such as muscle contraction, nerve impulse propagation, condensate dissolution, and chemical synthesis. Found in all known forms of life, ATP is often referred to as the "molecular unit of currency" of intracellular energy transfer. When consumed in metabolic processes, it converts either to adenosine diphosphate (ADP) or to adenosine monophosphate (AMP). Other processes regenerate ATP. The human body recycles its own body weight equivalent in ATP each day. It is also a precursor to DNA and RNA, and is used as a coenzyme. From the perspective of biochemistry, ATP is classified as a nucleoside triphosphate, which indicates that it consists of three components: a nitrogenous base (adenine), the sugar ribose, and the Polyphosphate, triphosphate. Structure ATP consists of an adenine attached by the 9-nitrogen atom to the 1′ carbon atom of a sugar (ribose), which i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetyl-CoA Carboxylase
Acetyl-CoA carboxylase (ACC) is a biotin-dependent enzyme () that catalyzes the irreversible carboxylation of acetyl-CoA to produce malonyl-CoA through its two catalytic activities, biotin carboxylase (BC) and carboxyltransferase (CT). ACC is a multi-subunit enzyme in most prokaryotes and in the chloroplasts of most plants and algae, whereas it is a large, multi-domain enzyme in the cytoplasm of most eukaryotes. The most important function of ACC is to provide the malonyl-CoA substrate for the biosynthesis of fatty acids. The activity of ACC can be controlled at the transcriptional level as well as by small molecule modulators and covalent modification. The human genome contains the genes for two different ACCs—'' ACACA'' and ''ACACB''. Structure Prokaryotes and plants have multi-subunit ACCs composed of several polypeptides. Biotin carboxylase (BC) activity, biotin carboxyl carrier protein (BCCP), and carboxyl transferase (CT) activity are each contained on a different s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haloferax Mediterranei
''Haloferax mediterranei'' is a species of archaea in the family Haloferacaceae. Discovery ''Haloferax mediterranei'' was discovered in 1983 in marine salterns in the village of Santa Pola, Spain. The species was initially named ''Halobacterium mediterranei'', then renamed ''Haloferax mediterranei'' in 1986. Haloferax mediterranei is the fastest-growing known member of the Halobacteriales under optimal laboratory conditions, but it is relatively rare in the environment. The full genome of ''H. mediterranei'' was sequenced in 2012. Metabolism and Growth Conditions ''Haloferax mediterranei'' is the fastest-growing archaeon in the Halobacteriales family, with generation times as low as 1.2 hours reported under optimal laboratory growth conditions. ''Haloferax mediterranei'' is able to use a variety of compounds as carbon and energy sources, and can accumulate materials to serve as a source of carbon and energy, as well as use organic and inorganic nitrogen sources. ''H. mediterrane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propionyl-CoA Carboxylase
Propionyl-CoA carboxylase (, PCC) catalyses the carboxylation reaction of propionyl-CoA in the mitochondrial matrix. PCC has been classified both as a ligase and a lyase. The enzyme is biotin-dependent. The product of the reaction is (S)-methylmalonyl CoA. : ATP + propionyl-CoA + HCO3− ADP + phosphate + (S)-methylmalonyl-CoA (S)-Methylmalonyl-CoA cannot be directly utilized by animals. It is acted upon by a racemase, yielding (R)-methylmalonyl-CoA, which is then converted into succinyl-CoA by methylmalonyl-CoA mutase (one of the few metabolic enzymes which requires vitamin B12 as a cofactor). Succinyl-CoA, a Krebs cycle intermediate, is further metabolized into fumarate, then malate, and then oxaloacetate. Oxaloacetate may be transported into the cytosol to form phosphoenol pyruvate and other gluconeogenic intermediates. Propionyl-CoA is therefore an important precursor to glucose. Propionyl-CoA is the end product of odd-chain fatty acid metabolism, including most methylated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biotin Carboxylase
In enzymology, a biotin carboxylase () is an enzyme that Catalysis, catalyzes the chemical reaction : ATP + biotin-carboxyl-carrier protein + CO2 \rightleftharpoons ADP + phosphate + carboxybiotin-carboxyl-carrier protein The three Substrate (biochemistry), substrates of this enzyme are Adenosine triphosphate, ATP, biotin-carboxyl-carrier protein (BCCP), and Carbon dioxide, CO2, whereas its three Product (chemistry), products are Adenosine diphosphate, ADP, phosphate, and carboxybiotin-carboxyl-carrier protein. The List of enzymes, systematic name of this enzyme class is biotin-carboxyl-carrier-protein:carbon-dioxide ligase (ADP-forming). This enzyme is also called biotin carboxylase (component of Acetyl-CoA carboxylase, acetyl CoA carboxylase). This enzyme participates in fatty acid biosynthesis. This enzyme participates in fatty acid biosynthesis by providing one of the catalytic functions of the Acetyl-CoA carboxylase complex. As previously mentioned, after the carboxybiot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coenzymes
A cofactor is a non-protein chemical compound or metallic ion that is required for an enzyme's role as a catalyst (a catalyst is a substance that increases the rate of a chemical reaction). Cofactors can be considered "helper molecules" that assist in biochemical transformations. The rates at which these happen are characterized in an area of study called enzyme kinetics. Cofactors typically differ from ligands in that they often derive their function by remaining bound. Cofactors can be divided into two types: inorganic ions and complex organic molecules called coenzymes. Coenzymes are mostly derived from vitamins and other organic essential nutrients in small amounts. (Note that some scientists limit the use of the term "cofactor" for inorganic substances; both types are included here.) Coenzymes are further divided into two types. The first is called a "prosthetic group", which consists of a coenzyme that is tightly (or even covalently) and permanently bound to a protein. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzymes
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecules known as product (chemistry), products. Almost all metabolism, metabolic processes in the cell (biology), cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme, pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are Ribozyme, catalytic RNA molecules, called ribozymes. Enzymes' Chemical specificity, specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolism
Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the conversion of food to building blocks for proteins, lipids, nucleic acids, and some carbohydrates; and the elimination of metabolic wastes. These enzyme-catalyzed reactions allow organisms to grow and reproduce, maintain their structures, and respond to their environments. The word metabolism can also refer to the sum of all chemical reactions that occur in living organisms, including digestion and the transportation of substances into and between different cells, in which case the above described set of reactions within the cells is called intermediary (or intermediate) metabolism. Metabolic reactions may be categorized as ''catabolic'' – the ''breaking down'' of compounds (for example, of glucose to pyruvate by ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
