n/a
17-484: N/a n/a n/a n a n/a n/a n/a n/a n/a Biotinidase ( EC 3.5.1.12 , amidohydrolase biotinidase , BTD ), also known as biotinase , is an enzyme that in humans is encoded by the BTD gene . The enzyme breaks down biotin amides, releasing free biotin and the amine. The main substrate is biocytin , or biotin linked to lysine . It is also capable of breaking apart biotin esters. This enzyme allows
34-437: A primary key of a database management system table , whose table definitions require a database design . In computability theory , the simplest numbering scheme is the assignment of natural numbers to a set of objects such as functions , rational numbers , graphs , or words in some formal language . A numbering can be used to transfer the idea of computability and related concepts, which are originally defined on
51-457: A person to be affected by the disorder. Most often, the parents of a child with an autosomal recessive disorder are not affected but are carriers of one copy of the altered gene. BTD gene variant database [REDACTED] This article incorporates public domain material from Genetics Home Reference . United States National Library of Medicine . Enzyme Commission number The Enzyme Commission number ( EC number )
68-623: A progressively finer classification of the enzyme. Preliminary EC numbers exist and have an 'n' as part of the fourth (serial) digit (e.g. EC 3.5.1.n3). For example, the tripeptide aminopeptidases have the code "EC 3.4.11.4", whose components indicate the following groups of enzymes: NB:The enzyme classification number is different from the 'FORMAT NUMBER' Oxidation /reduction reactions; transfer of H and O atoms or electrons from one substance to another Similarity between enzymatic reactions can be calculated by using bond changes, reaction centres or substructure metrics (formerly EC-BLAST], now
85-421: Is a numerical classification scheme for enzymes , based on the chemical reactions they catalyze . As a system of enzyme nomenclature , every EC number is associated with a recommended name for the corresponding enzyme-catalyzed reaction. EC numbers do not specify enzymes but enzyme-catalyzed reactions. If different enzymes (for instance from different organisms) catalyze the same reaction, then they receive
102-465: Is attached to these carboxylase enzymes through an amino acid (the building material of proteins) called lysine , forming a complex called biocytin . Biotinidase removes biotin from biocytin and makes it available to be reused by other enzymes. Biotin , sometimes called vitamin H, is an important water-soluble vitamin that aids in the metabolism of fats , carbohydrates and proteins . The human body cannot produce biotin, but it can obtain it from
119-494: The BTD gene cause biotinidase deficiency. Approximately 100 mutations in the BTD gene that lead to biotinidase deficiency have been discovered. These mutations either prevent the enzyme from being made or cause the enzyme that is produced to be nonfunctional. This condition is inherited in an autosomal recessive pattern, which means two copies of the gene in each cell must be altered for
136-562: The EMBL-EBI Enzyme Portal). Before the development of the EC number system, enzymes were named in an arbitrary fashion, and names like old yellow enzyme and malic enzyme that give little or no clue as to what reaction was catalyzed were in common use. Most of these names have fallen into disuse, though a few, especially proteolyic enzymes with very low specificity, such as pepsin and papain , are still used, as rational classification on
153-533: The Enzyme Commission was dissolved at that time, though its name lives on in the term EC Number . The current sixth edition, published by the International Union of Biochemistry and Molecular Biology in 1992 as the last version published as a printed book, contains 3196 different enzymes. Supplements 1-4 were published 1993–1999. Subsequent supplements have been published electronically, at the website of
170-618: The Nomenclature Committee of the International Union of Biochemistry and Molecular Biology. In August 2018, the IUBMB modified the system by adding the top-level EC 7 category containing translocases. Numbering scheme There are many different numbering schemes for assigning nominal numbers to entities. These generally require an agreed set of rules, or a central coordinator. The schemes can be considered to be examples of
187-584: The basis of specificity has been very difficult. By the 1950s the chaos was becoming intolerable, and after Hoffman-Ostenhof and Dixon and Webb had proposed somewhat similar schemes for classifying enzyme-catalyzed reactions, the International Congress of Biochemistry in Brussels set up the Commission on Enzymes under the chairmanship of Malcolm Dixon in 1955. The first version was published in 1961, and
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#1732854819990204-417: The body to use and to recycle the B vitamin biotin , sometimes called vitamin H. Biotinidase extracts biotin from food because the body needs biotin in its free, unattached form. This enzyme also recycles biotin from enzymes in the body that use it as a helper component in order to function. These enzymes, known as carboxylases , are important in the processing of fats , carbohydrates , and proteins . Biotin
221-407: The diet, internal recycling and at some extent from intestinal bacteria. Biotin deficiency can result in behavioral disorders, lack of coordination, learning disabilities and seizure. Unlike most vitamins, which are noncovalently bound to enzymes, biotin is chemically linked ( covalently bound), and therefore cannot be easily removed from the enzyme denaturation . Without biotinidase activity,
238-410: The natural numbers using computable functions , to these different types of objects. A simple extension is to assign cardinal numbers to physical objects according to the choice of some base of reference and of measurement units for counting or measuring these objects within a given precision. In such case, numbering is a kind of classification , i.e. assigning a numeric property to each object of
255-512: The proper processing of proteins, fats, and carbohydrates. Individuals lacking biotinidase activity can still have normal carboxylases if they ingest small amounts of biotin. Approximately 1 in 60,000 newborns are affected by profound (less than 10 percent of normal enzyme activity) or partial (10-30 percent of normal enzyme activity) biotinidase deficiency. The BTD gene is located on the short (p) arm of chromosome 3 at position 25, from base pair 15,618,326 to base pair 15,662,328. Mutations in
272-470: The same EC number. Furthermore, through convergent evolution , completely different protein folds can catalyze an identical reaction (these are sometimes called non-homologous isofunctional enzymes ) and therefore would be assigned the same EC number. By contrast, UniProt identifiers uniquely specify a protein by its amino acid sequence. Every enzyme code consists of the letters "EC" followed by four numbers separated by periods. Those numbers represent
289-489: The vitamin biotin cannot be separated from foods and therefore cannot be used by the body. Biotinidase deficiency is an inherited disorder caused by mutations in the BTD gene. When biotinidase activity is deficient, biotin can be neither recycled within the body nor removed from ingested food. Nor can biotin be recycled from enzymes to which it is bound. Deficient biotinidase activity causes specific metabolic enzymes, called carboxylases, to be nonfunctional, inhibiting
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