4.2.1.110	1,5-anhydro-D-fructose	-	Phanerodontia chrysosporium	2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one + H2O	microthecin + H2O	?	383008	
4.2.1.110	1,5-anhydro-D-fructose	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. 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]. The other enzymes involved in this pathway are EC 4.2.1.111 (1,5-anhydro-D-fructose dehydratase), EC 4.2.2.13 (exo-(1,4)-alpha-D-glucan lyase) and EC 5.3.3.15 (ascopyrone tautomerase). This is a bifunctional enzyme that acts as both a lyase and as an isomerase. Differs from EC 4.2.1.111, which can carry out only reaction 1a	Sarcodontia unicolor	2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one + H2O	i.e. microthecin	?	383008	
4.2.1.110	1,5-anhydro-D-fructose	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. 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. The other enzymes involved in this pathway are EC 4.2.1.111 (1,5-anhydro-D-fructose dehydratase), EC 4.2.2.13 (exo-(1,4)-alpha-D-glucan lyase) and EC 5.3.3.15 (ascopyrone tautomerase). This is a bifunctional enzyme that acts as both a lyase and as an isomerase. Differs from EC 4.2.1.111, which can carry out only reaction 1a	Gracilariopsis lemaneiformis	2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one + H2O	i.e. microthecin	?	383008	
4.2.1.110	1,5-anhydro-D-fructose	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. 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. The other enzymes involved in this pathway are EC 4.2.1.111 (1,5-anhydro-D-fructose dehydratase), EC 4.2.2.13 (exo-(1,4)-alpha-D-glucan lyase) and EC 5.3.3.15 (ascopyrone tautomerase). This is a bifunctional enzyme that acts as both a lyase and as an isomerase. Differs from EC 4.2.1.111, which can carry out only reaction 1a	Morchella costata	2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one + H2O	i.e. microthecin	?	383008	
4.2.1.110	1,5-anhydro-D-fructose	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. 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. The other enzymes involved in this pathway are EC 4.2.1.111 (1,5-anhydro-D-fructose dehydratase), EC 4.2.2.13 (exo-(1,4)-alpha-D-glucan lyase) and EC 5.3.3.15 (ascopyrone tautomerase). This is a bifunctional enzyme that acts as both a lyase and as an isomerase. Differs from EC 4.2.1.111, which can carry out only reaction 1a	Morchella vulgaris	2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one + H2O	i.e. microthecin	?	383008	
4.2.1.110	1,5-anhydro-D-fructose	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. 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. The other enzymes involved in this pathway are EC 4.2.1.111 (1,5-anhydro-D-fructose dehydratase), EC 4.2.2.13 (exo-(1,4)-alpha-D-glucan lyase) and EC 5.3.3.15 (ascopyrone tautomerase). This is a bifunctional enzyme that acts as both a lyase and as an isomerase. Differs from EC 4.2.1.111, which can carry out only reaction 1a	Phanerodontia chrysosporium	2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one + H2O	i.e. microthecin	?	383008	
4.2.1.110	1,5-anhydro-D-fructose	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. 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. The other enzymes involved in this pathway are EC 4.2.1.111 (1,5-anhydro-D-fructose dehydratase), EC 4.2.2.13 (exo-(1,4)-alpha-D-glucan lyase) and EC 5.3.3.15 (ascopyrone tautomerase). This is a bifunctional enzyme that acts as both a lyase and as an isomerase. Differs from EC 4.2.1.111, which can carry out only reaction 1a	Microthecium compressum	2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one + H2O	i.e. microthecin	?	383008	
4.2.1.110	1,5-anhydro-D-fructose	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. 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. The other enzymes involved in this pathway are EC 4.2.1.111 (1,5-anhydro-D-fructose dehydratase), EC 4.2.2.13 (exo-(1,4)-alpha-D-glucan lyase) and EC 5.3.3.15 (ascopyrone tautomerase). This is a bifunctional enzyme that acts as both a lyase and as an isomerase. Differs from EC 4.2.1.111, which can carry out only reaction 1a	Microthecium sobelii	2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one + H2O	i.e. microthecin	?	383008	
4.2.1.110	1,5-anhydro-D-fructose	formation of microthecin is irreversible. 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. 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. The other enzymes involved in this pathway are EC 4.2.1.111 (1,5-anhydro-D-fructose dehydratase), EC 4.2.2.13 (exo-(1,4)-alpha-D-glucan lyase) and EC 5.3.3.15 (ascopyrone tautomerase). This is a bifunctional enzyme that acts as both a lyase and as an isomerase. Differs from EC 4.2.1.111, which can carry out only reaction 1a	Phanerodontia chrysosporium	2-hydroxy-2-(hydroxymethyl)-2H-pyran-3(6H)-one + H2O	i.e. microthecin	ir	383008	
4.2.1.110	1,5-D-anhydrofructose	dehydration reaction most likely follows an elimination mechanism, where Zn2+ acts as a Lewis acid polarizing the C2 oxo group of 1,5-D-anhydrofructose. The reaction intermediate ascopyrone M shows binding of this compound at two different sites, with direct coordination to Zn2+ in the propeller domain and as second sphere ligand of the metal ion in the cupin domain	Phanerodontia chrysosporium	microthecin	-	?	429580