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Your query returned 2 entries. Printable version
EC | 4.2.1.110 | ||||||||||
Accepted name: | aldos-2-ulose dehydratase | ||||||||||
Reaction: | 1,5-anhydro-D-fructose = 2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one
+ H2O (overall reaction) (1a) 1,5-anhydro-D-fructose = 1,5-anhydro-4-deoxy-D-glycero-hex-3-en-2-ulose + H2O (1b) 1,5-anhydro-4-deoxy-D-glycero-hex-3-en-2-ulose = 2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one |
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For diagram of the anhydrofructose pathway, click here | |||||||||||
Glossary: | 1,5-anhydro-D-fructose = 1,5-anhydro-D-arabino-hex-2-ulose = (4S,5S,6R)-4,5-dihydroxy-6-(hydroxymethyl)dihydro-2H-pyran-3(4H)-one ascopyrone M = 1,5-anhydro-4-deoxy-D-glycero-hex-3-en-2-ulose = (6S)-4-hydroxy-6-(hydroxymethyl)-2H-pyran-3(6H)-one microthecin = 2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one |
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Other name(s): | pyranosone dehydratase; AUDH; 1,5-anhydro-D-fructose dehydratase (microthecin-forming) | ||||||||||
Systematic name: | 1,5-anhydro-D-fructose hydro-lyase (microthecin-forming) | ||||||||||
Comments: | This enzyme catalyses two of the steps in the anhydrofructose pathway, which leads to the degradation of glycogen and starch via 1,5-anhydro-D-fructose [1,2]. Aldose-2-uloses such as 2-dehydroglucose can also act as substrates, but more slowly [1,2,4]. This is a bifunctional enzyme that acts as both a lyase and as an isomerase [2]. Differs from EC 4.2.1.111, which can carry out only reaction (1a), is inhibited by its product and requires metal ions for activity [1]. | ||||||||||
Links to other databases: | BRENDA, EAWAG-BBD, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 101920-80-3 | ||||||||||
References: |
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EC | 4.2.1.111 | ||||||||||
Accepted name: | 1,5-anhydro-D-fructose dehydratase | ||||||||||
Reaction: | 1,5-anhydro-D-fructose = 1,5-anhydro-4-deoxy-D-glycero-hex-3-en-2-ulose + H2O | ||||||||||
For diagram of the anhydrofructose pathway, click here | |||||||||||
Glossary: | 1,5-anhydro-D-fructose = 1,5-anhydro-D-arabino-hex-2-ulose = (4S,5S,6R)-4,5-dihydroxy-6-(hydroxymethyl)dihydro-2H-pyran-3(4H)-one ascopyrone M = 1,5-anhydro-4-deoxy-D-glycero-hex-3-en-2-ulose = (6S)-4-hydroxy-6-(hydroxymethyl)-2H-pyran-3(6H)-one |
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Other name(s): | 1,5-anhydro-D-fructose 4-dehydratase; 1,5-anhydro-D-fructose hydrolyase; 1,5-anhydro-D-arabino-hex-2-ulose dehydratase; AFDH; AF dehydratase; 1,5-anhydro-D-fructose hydro-lyase | ||||||||||
Systematic name: | 1,5-anhydro-D-fructose hydro-lyase (ascopyrone-M-forming) | ||||||||||
Comments: | This enzyme catalyses one of the steps in the anhydrofructose pathway, which leads to the degradation of glycogen and starch via 1,5-anhydro-D-fructose [1,2]. The other enzymes involved in this pathway are EC 4.2.1.110 (aldos-2-ulose dehydratase), EC 4.2.2.13 [exo-(1→4)-α-D-glucan lyase] and EC 5.3.2.7 (ascopyrone tautomerase). Requires divalent (Ca2+ or Mg2+) or monovalent cations (Na+) for optimal activity. Unlike EC 4.2.1.110, the enzyme is specific for 1,5-anhydro-D-fructose as substrate and shows no activity towards aldose-2-uloses such as 2-dehydroglucose [1,2,3]. In addition, it is inhibited by its end-product ascopyrone M [2] and it cannot convert ascopyrone M into microthecin, as can EC 4.2.1.110. | ||||||||||
Links to other databases: | BRENDA, EAWAG-BBD, EXPASY, KEGG, MetaCyc | ||||||||||
References: |
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