Isomerases

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Transferases
Enzyme classification
EC, category 5.-.-.-
Response type Isomerization
Occurrence
Parent taxon Creature

Isomerases are enzymes of the fifth enzyme class according to the systematic nomenclature of the enzyme commission of the International Union of Biochemistry (IUB) and catalyze the isomerization reactions, i.e. the conversion of a compound into an isomeric structure. Isomers are molecules with the same molecular formula but different absolute configuration or structural formula . Racemases catalyze racemization reactions in which a hydrogen is rearranged on the single chiral carbon atom of a compound. An important biochemical isomerization reaction is the aldose - ketose - rearrangement .

Isomerases are categorized in the EC number classification system under EC  5.-.-.- .

classification

 EC number  feature Group name Examples
EC  5.1.-.- Configuration inversion Racemases and epimerases UDP-glucose-4-epimerase
EC  5.2.-.- Configuration inversion cis-trans isomerases Peptidyl prolyl cis trans isomerase
EC  5.3.-.- Oxidoreduction Intramolecular oxidoreductases Glucose isomerase

Triosephosphate isomerase

EC  5.4.-.- Constitutional isomers Mutases Methylmalonyl-CoA mutase
EC  5.5.-.- Intramolecular lyases Muconate cycloisomerase
EC  5.6.-.- Changing polypeptides or DNA Topoisomerases

Other classes of enzymes

Individual evidence

  1. ^ A b Albert Gossauer: Structure and reactivity of biomolecules , Verlag Helvetica Chimica Acta, Zurich, 2006, p. 450, ISBN 978-3-906390-29-1 .