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 nicotinamidase () 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 ...
:nicotinamide + H
2O
nicotinate + NH
3
Thus, the two
substrates of this enzyme are
nicotinamide
Niacinamide or Nicotinamide (NAM) is a form of vitamin B3 found in food and used as a dietary supplement and medication. As a supplement, it is used by mouth to prevent and treat pellagra (niacin deficiency). While nicotinic acid (niacin) may ...
and
H2O, whereas its two
products are
nicotinate
Niacin, also known as nicotinic acid, is an organic compound and a form of vitamin B3, an essential human nutrient. It can be manufactured by plants and animals from the amino acid tryptophan. Niacin is obtained in the diet from a variet ...
and
NH3.
This enzyme belongs to the family of
hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amides. The
systematic name of this enzyme class is nicotinamide amidohydrolase. Other names in common use include nicotinamide deaminase, nicotinamide amidase, and YNDase. This enzyme participates in
nicotinate and nicotinamide metabolism
Nicotinamide adenine dinucleotide (NAD) is a coenzyme central to metabolism. Found in all living cells, NAD is called a dinucleotide because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an aden ...
.
Structural studies
As of late 2007, 3
structures have been solved for this class of enzymes, with
PDB accession codes , , and .
References
*
*
EC 3.5.1
Enzymes of known structure
{{3.5-enzyme-stub