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Thiamine pyrophosphate (TPP or ThPP), or thiamine diphosphate (ThDP), or cocarboxylase [1] is a thiamine (vitamin B 1) derivative which is produced by the enzyme thiamine diphosphokinase. Thiamine pyrophosphate is a cofactor that is present in all living systems, in which it catalyzes several biochemical reactions.
Thiamine, also known as thiamin and vitamin B 1, is a vitamin, an essential micronutrient for humans and animals. [3] [4] It is found in food and commercially synthesized to be a dietary supplement or medication. [1] [5] Phosphorylated forms of thiamine are required for some metabolic reactions, including the breakdown of glucose and amino ...
Pyruvate decarboxylation requires a few cofactors in addition to the enzymes that make up the complex. The first is thiamine pyrophosphate (TPP), which is used by pyruvate dehydrogenase to oxidize pyruvate and to form a hydroxyethyl-TPP intermediate. This intermediate is taken up by dihydrolipoyl transacetylase and reacted with a second ...
The oxidative decarboxylation reaction is catalyzed by pyruvate dehydrogenase system, which includes three different enzymes: pyruvate dehydrogenase (E1), dihydrolipoamide acetyltransferase (E2), dihydrolipoamide dehydrogenase (E3), six cofactors: thiamine pyrophosphate (TPP), lipoamide, coenzyme A (CoA), flavin adenine dinucleotide (FAD ...
Pyruvate dehydrogenase is an enzyme that catalyzes the reaction of pyruvate and a lipoamide to give the acetylated dihydrolipoamide and carbon dioxide. The conversion requires the coenzyme thiamine pyrophosphate. Pyruvate dehydrogenase is usually encountered as a component, referred to as E1, of the pyruvate dehydrogenase complex (PDC). PDC ...
It serves as a riboswitch [1] [2] that binds thiamine pyrophosphate (TPP) directly and modulates gene expression through a variety of mechanisms in archaea, bacteria and eukaryotes. [3] [4] [5] TPP is the active form of thiamine (vitamin B 1), an essential coenzyme synthesised by coupling of pyrimidine and thiazole moieties in bacteria.
Intracellular anions are able to promote folate derivative uptake. A bidirectional anion antiport mechanism for RFC family members is favored. In support of this notion, RFC1 has been shown to catalyze efflux of thiamin pyrophosphate (TPP). [3] [4]
Initially, pyruvate and thiamine pyrophosphate (TPP or vitamin B 1) are bound by pyruvate dehydrogenase subunits. [1] The thiazolium ring of TPP is in a zwitterionic form, and the anionic C2 carbon performs a nucleophilic attack on the C2 (ketone) carbonyl of pyruvate.