Cannabidiolic acid synthase (, ''CBDA synthase'') is an
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecule ...
with
systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature.
A semisystematic name or semitrivial ...
''cannabigerolate:oxygen oxidoreductase (cyclizing, cannabidiolate-forming)''.
It is an
oxidoreductase
In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule, the reductant, also called the electron donor, to another, the oxidant, also called the electron acceptor. This group of enzymes usually ...
found in ''
Cannabis sativa
''Cannabis sativa'' is an annual herbaceous flowering plant indigenous to Eastern Asia, but now of cosmopolitan distribution due to widespread cultivation. It has been cultivated throughout recorded history, used as a source of industrial fiber ...
'' that catalyses the formation of
cannabidiolate, a
carboxylated precursor
Precursor or Precursors may refer to:
*Precursor (religion), a forerunner, predecessor
** The Precursor, John the Baptist
Science and technology
* Precursor (bird), a hypothesized genus of fossil birds that was composed of fossilized parts of un ...
of
cannabidiol
Cannabidiol (CBD) is a phytocannabinoid discovered in 1940. It is one of 113 identified cannabinoids in cannabis plants, along with tetrahydrocannabinol (THC), and accounts for up to 40% of the plant's extract. , clinical research on CBD inc ...
.
Enzyme structure
Cannabidiolic acid synthase consists of a single protein with a molecular mass of 74 kDa.
Its amino acid sequence is partly (40-50%) homologous to several other oxidoreductases,
such as
berberine bridge enzyme
Berberine is a quaternary ammonium salt from the protoberberine group of benzylisoquinoline alkaloids found in such plants as ''Berberis vulgaris'' (barberry), ''Berberis aristata'' (tree turmeric), ''Mahonia aquifolium'' (Oregon grape), ''Hydras ...
in ''
Eschscholzia californica'' and
Nectarin V in ''
Nicotiana langsdorffii X N. sanderae''.
CBDA synthase has four binding sites; two for
FAD and two for the substrate.
Enzyme function
Cannabidiolic acid synthase
catalyses the production of
cannabidiolate predominantly from
cannabigerolate by stereospecific oxidative cyclization of the
geranyl group of
cannabigerolic acid according to the following
chemical reaction
A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and break ...
:
:
cannabigerolate + O
2 →
cannabidiolate + H
2O
2
Cannabinerolate can also be used as a substrate, but with lower efficiency (
KM=0.137 mM) than
cannabigerolate (K
M=0.206 mM). It
covalently
A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between atom ...
binds FAD, and does require coenzymes & molecular oxygen for the oxidocyclization reaction.
The optimum pH for CBDA synthase is 5.0.
References
External links
*
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