In
enzymology
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...
, a precorrin-4 C11-methyltransferase () is an
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...
that
catalyzes
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...
the
chemical reaction
A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the pos ...
:S-adenosyl-L-methionine + precorrin-4
S-adenosyl-L-homocysteine + precorrin-5
The two
substrates of this enzyme are
S-adenosyl methionine
''S''-Adenosyl methionine (SAM), also known under the commercial names of SAMe, SAM-e, or AdoMet, is a common cosubstrate involved in methyl group transfers, transsulfuration, and aminopropylation. Although these anabolic reactions occur throug ...
and
precorrin 4; its two
products are
S-adenosylhomocysteine and
precorrin 5.
This enzyme belongs to the family of
transferase
A transferase is any one of a class of enzymes that catalyse the transfer of specific functional groups (e.g. a methyl or glycosyl group) from one molecule (called the donor) to another (called the acceptor). They are involved in hundreds of di ...
s, specifically those transferring one-carbon group methyltransferases. The
systematic name of this enzyme class is S-adenosyl-L-methionine:precorrin-4 C11 methyltransferase. Other names in common use include precorrin-3 methylase, and CobM. It is part of the biosynthetic pathway to
cobalamin (vitamin B
12) in
aerobic bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...
.
See also
*
Cobalamin biosynthesis
Cobalamin biosynthesis is the process by which bacteria and archea make Vitamin B12, cobalamin, vitamin B12. Many steps are involved in converting aminolevulinic acid via uroporphyrinogen III and adenosylcobyric acid to the final forms in which it ...
Structural studies
As of late 2007, two
structures have been solved for this class of enzymes, with
PDB accession codes and .
References
*
*
EC 2.1.1
Enzymes of known structure
{{2.1-enzyme-stub