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Your query returned 4 entries. Printable version
EC | 1.1.1.249 | ||||||||||||||||||
Deleted entry: | Provisional entry deleted. Revised and reinstated as EC 2.5.1.46 deoxyhypusine synthase | ||||||||||||||||||
EC | 1.14.99.29 | ||||||||||||||||||
Accepted name: | deoxyhypusine monooxygenase | ||||||||||||||||||
Reaction: | [eIF5A]-deoxyhypusine + reduced acceptor + O2 = [eIF5A]-hypusine + acceptor + H2O | ||||||||||||||||||
For diagram of reaction, click here | |||||||||||||||||||
Glossary: | deoxyhypusine = N6-(4-aminobutyl)-L-lysine hypusine = N6-[(R)-4-amino-2-hydroxybutyl]-L-lysine |
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Other name(s): | deoxyhypusine hydroxylase; deoxyhypusine dioxygenase | ||||||||||||||||||
Systematic name: | deoxyhypusine,hydrogen-donor:oxygen oxidoreductase (2-hydroxylating) | ||||||||||||||||||
Comments: | The enzyme catalyses the final step in the formation of the amino acid hypusine in the eukaryotic initiation factor 5A. | ||||||||||||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 101920-83-6 | ||||||||||||||||||
References: |
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EC | 2.5.1.45 | ||||||||||||||||||
Accepted name: | homospermidine synthase (spermidine-specific) | ||||||||||||||||||
Reaction: | spermidine + putrescine = sym-homospermidine + propane-1,3-diamine | ||||||||||||||||||
For diagram of reaction, click here | |||||||||||||||||||
Glossary: | sym-homospermidine = N1-(4-aminobutyl)butane-1,4-diamine putrescine = butane-1,4-diamine spermidine = N1-(3-aminopropyl)butane-1,4-diamine |
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Systematic name: | spermidine:putrescine 4-aminobutyltransferase (propane-1,3-diamine-forming) | ||||||||||||||||||
Comments: | A eukaryotic enzyme found in plants. The reaction occurs in three steps, with some of the intermediates presumably remaining enzyme-bound: (a) NAD+-dependent dehydrogenation of spermidine to 4-iminobutan-1-amine, (b) attack by water forming 4-aminobutanal (and releasing propane-1,3-diamine), and (c) condensation of 4-aminobutanal with purescine, which forms homospermidine and restores NAD+. This enzyme is more specific than EC 2.5.1.44, homospermidine synthase, which is found in bacteria, as it cannot use putrescine as donor of the 4-aminobutyl group. Forms part of the biosynthetic pathway of the poisonous pyrrolizidine alkaloids of the ragworts (Senecio). | ||||||||||||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc | ||||||||||||||||||
References: |
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EC | 2.5.1.46 | ||||||||||||||||||
Accepted name: | deoxyhypusine synthase | ||||||||||||||||||
Reaction: | [eIF5A-precursor]-lysine + spermidine = [eIF5A-precursor]-deoxyhypusine + propane-1,3-diamine (overall reaction) (1a) spermidine + NAD+ = dehydrospermidine + NADH (1b) dehydrospermidine + [enzyme]-lysine = N-(4-aminobutylidene)-[enzyme]-lysine + propane-1,3-diamine (1c) N-(4-aminobutylidene)-[enzyme]-lysine + [eIF5A-precursor]-lysine = N-(4-aminobutylidene)-[eIF5A-precursor]-lysine + [enzyme]-lysine (1d) N-(4-aminobutylidene)-[eIF5A-precursor]-lysine + NADH + H+ = [eIF5A-precursor]-deoxyhypusine + NAD+ |
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For diagram of reaction, click here | |||||||||||||||||||
Glossary: | deoxyhypusine = N6-(4-aminobutyl)-L-lysine hypusine = N6-[(R)-4-amino-2-hydroxybutyl]-L-lysine spermidine = N-(3-aminopropyl)butane-1,4-diamine |
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Other name(s): | spermidine:eIF5A-lysine 4-aminobutyltransferase (propane-1,3-diamine-forming) | ||||||||||||||||||
Systematic name: | [eIF5A-precursor]-lysine:spermidine 4-aminobutyltransferase (propane-1,3-diamine-forming) | ||||||||||||||||||
Comments: | The eukaryotic initiation factor eIF5A contains a hypusine residue that is essential for activity. This enzyme catalyses the first reaction of hypusine formation from one specific lysine residue of the eIF5A precursor. The reaction occurs in four steps: NAD+-dependent dehydrogenation of spermidine (1a), formation of an enzyme-imine intermediate by transfer of the 4-aminobutylidene group from dehydrospermidine to the active site lysine residue (Lys329 for the human enzyme; 1b), transfer of the same 4-aminobutylidene group from the enzyme intermediate to the e1F5A precursor (1c), reduction of the e1F5A-imine intermediate to form a deoxyhypusine residue (1d). Hence the overall reaction is transfer of a 4-aminobutyl group. For the plant enzyme, homospermidine can substitute for spermidine and putrescine can substitute for the lysine residue of the eIF5A precursor. Hypusine is formed from deoxyhypusine by the action of EC 1.14.99.29, deoxyhypusine monooxygenase. | ||||||||||||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 127069-31-2 | ||||||||||||||||||
References: |
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