EC Number |
Substrates |
Organism |
Products |
Reversibility |
---|
1.3.1.112 | 2 cyanidin + 4 NADPH + 4 H+ |
- |
Vitis vinifera |
(+)-epicatechin + (-)-catechin + 4 NADP+ |
- |
? |
1.3.1.112 | 2 cyanidin + 4 NADPH + 4 H+ |
- |
Vitis vinifera |
(+)-epicatechin + (-)-catechin + 4 NADP+ |
the relative concentration of catechin versus epicatechin remains nearly constant and is close to 1 |
? |
1.3.1.112 | cyanidin + 2 NADPH + 2 H+ |
- |
Vitis vinifera |
epicatechin + 2 NADP+ |
- |
? |
1.3.1.112 | delphinidin + 2 NADPH + 2 H+ |
- |
Vitis vinifera |
epigallocatechin + 2 NADP+ |
- |
? |
1.3.1.112 | more |
ANR is strictly pro-S stereospecific and the reaction mechanism involves two hydride transfers from two distinct NADPH molecules. ANR produces a 50:50 mixture of 2,3-cis and 2,3-trans flavan-3-ols, i.e. 2S,3S- and 2S,3R-flavan-3-ols |
Vitis vinifera |
? |
- |
? |
1.3.1.112 | more |
hyperbolic and rapid-equilibrium ordered mechanism, with NADPH binding first. The most likely mechanism is sequential ordered Bi Uni Uni Bi, with NADPH binding first and NADP+ released last, and internal conversion of the first ternary complex, i.e. that associated with the first hydride transfer, is rate-limiting |
Vitis vinifera |
? |
- |
? |
1.3.1.112 | more |
in the presence of excess NADP+, ANR acts as a flavan-3-ol C3-epimerase, but only with 2R-flavan-3-ols, not with 2S-flavan-3-ols produced by the enzyme in the forward reaction. C3-epimerization should be achieved by tautomerization between the two hydride transfers and this produces a quinone methide intermediate which serves as C4 target of the second hydride transfer, avoiding any stereospecific modification of carbon 3. The inversion of C2 stereochemistry required for reverse epimerization suggests that the 2S configuration induces an irreversible product dissociation |
Vitis vinifera |
? |
- |
? |
1.3.1.112 | pelargonidin + 2 NADPH + 2 H+ |
- |
Vitis vinifera |
epiafzelechin + 2 NADP+ |
- |
? |
1.3.1.112 | peonidin + 2 NADPH + 2 H+ |
- |
Vitis vinifera |
(2S,3S)-3,5,7-trihydroxy-2-(4-hydroxy-3-methoxyphenyl)-2,3-dihydro-1-benzopyran-1-ium + 2 NADP+ |
- |
? |
1.3.1.112 | petunidin + 2 NADPH + 2 H+ |
- |
Vitis vinifera |
? + 2 NADP+ |
- |
? |