Leucoanthocyanidin reductase
Encyclopedia
In enzymology, a leucoanthocyanidin reductase (LAR, aka leucocyanidin reductase or LCR) is an enzyme
that catalyzes
the chemical reaction
-catechin + NADP+ + H2O
2,3-trans-3,4-cis-leucocyanidin + NADPH + H+
The 3 substrates
of this enzyme are (2R,3S)-catechin, NADP+
, and H2O
, whereas its 3 products
are 2,3-trans-3,4-cis-leucocyanidin, NADPH
, and H+
.
This enzyme belongs to the family of oxidoreductase
s, specifically those acting on CH or CH2 group with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is (2R,3S)-catechin:NADP+ 4-oxidoreductase. This enzyme is also called leucocyanidin reductase. This enzyme participates in flavonoid biosynthesis
.
The enzyme can be found in the plant Hedysarum sulphurescens
and in Vitis vinifera
(grape).
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that catalyzes
Catalysis
Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself. A catalyst may participate in multiple chemical transformations....
the chemical reaction
Chemical reaction
A chemical reaction is a process that leads to the transformation of one set of chemical substances to another. Chemical reactions can be either spontaneous, requiring no input of energy, or non-spontaneous, typically following the input of some type of energy, such as heat, light or electricity...
-catechin + NADP+ + H2O
2,3-trans-3,4-cis-leucocyanidin + NADPH + H+The 3 substrates
Substrate (biochemistry)
In biochemistry, a substrate is a molecule upon which an enzyme acts. Enzymes catalyze chemical reactions involving the substrate. In the case of a single substrate, the substrate binds with the enzyme active site, and an enzyme-substrate complex is formed. The substrate is transformed into one or...
of this enzyme are (2R,3S)-catechin, NADP+
Nicotinamide adenine dinucleotide phosphate
Nicotinamide adenine dinucleotide phosphate, abbreviated NADP or TPN in older notation , is a coenzyme used in anabolic reactions, such as lipid and nucleic acid synthesis, which require NADPH as a reducing agent....
, and H2O
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
, whereas its 3 products
Product (chemistry)
Product are formed during chemical reactions as reagents are consumed. Products have lower energy than the reagents and are produced during the reaction according to the second law of thermodynamics. The released energy comes from changes in chemical bonds between atoms in reagent molecules and...
are 2,3-trans-3,4-cis-leucocyanidin, NADPH
Nicotinamide adenine dinucleotide phosphate
Nicotinamide adenine dinucleotide phosphate, abbreviated NADP or TPN in older notation , is a coenzyme used in anabolic reactions, such as lipid and nucleic acid synthesis, which require NADPH as a reducing agent....
, and H+
Hydrogen ion
Hydrogen ion is recommended by IUPAC as a general term for all ions of hydrogen and its isotopes.Depending on the charge of the ion, two different classes can be distinguished: positively charged ions and negatively charged ions....
.
This enzyme belongs to the family of oxidoreductase
Oxidoreductase
In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule to another...
s, specifically those acting on CH or CH2 group with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is (2R,3S)-catechin:NADP+ 4-oxidoreductase. This enzyme is also called leucocyanidin reductase. This enzyme participates in flavonoid biosynthesis
Flavonoid biosynthesis
Flavonoids are synthesized by the phenylpropanoid metabolic pathway in which the amino acid phenylalanine is used to produce 4-coumaroyl-CoA. This can be combined with malonyl-CoA to yield the true backbone of flavonoids, a group of compounds called chalcones, which contain two phenyl rings...
.
The enzyme can be found in the plant Hedysarum sulphurescens
Hedysarum sulphurescens
Hedysarum sulphurescens, the yellow sweetvetch, is a perennial herb species.Leucocyanidin reductase uses 2,3-trans-3,4-cis-leucocyanidin to produce -catechin and is the first enzyme in the proanthocyanidins -specific pathway. Its activity has been measured in leaves, flowers, and seeds of H....
and in Vitis vinifera
Vitis vinifera
Vitis vinifera is a species of Vitis, native to the Mediterranean region, central Europe, and southwestern Asia, from Morocco and Portugal north to southern Germany and east to northern Iran....
(grape).