Samrat Prithviraj Chauhan Government College
Department of chemistry
Discovery of Coenzyme A
Structure of Coenzyme A
Biosynthesis of Coenzyme A
Function of Coenzyme A
DISCOVERY OF COENZYME A
Coenzyme A was identified by Fritz Lipmann in 1946, who also later gave it
Lipmann initially intended to study acetyl transfer in animals, and from
these experiments he noticed a unique factor that was not present in
enzyme extracts but was evident in all organs of the animals.
He was able to isolate and purify the factor from pig liver and discovered
that its function was related to a coenzyme that was active in choline
The coenzyme was named coenzyme A to stand for "activation of acetate".
In 1953, Fritz Lipmann won the Nobel Prize in Physiology or Medicine "for
his discovery of co-enzyme A and its importance for intermediary
Fritz Albert Lipmann
Coenzyme A (CoA, SHCoA, CoASH) is
a coenzyme, notable for its role in the synthesis
and oxidation of fatty acids and the oxidation
of pyruvate in the citric acid cycle .All genomes
sequenced to date encode enzymes that use
coenzyme A as a substrate, and around 4% of
cellular enzymes use it as a substrate.
It is a part of enzyme which consist biological
acylation. It helps in transferring the acyl group form
the compound to another.
On enzymatic hydrolysis Coenzyme A gives
pantothenic acid, adenosine phosphate and an
unidentified sulphur containing product.
Further, it was observed that one molecule
of adenosine and three molecule of
phosphate were produced for each mole of
pantothenic acid. Out of three molecules of
phosphates one was found to be
present as monophosphate and the other
two as pyrophosphate ester grouping.
The monophosphate ester was found to be
present 3'-position of ribose sugar. The
pyrophosphate group is present as
a bridge between the 5'-position and 4'-
position of adenosine and pantothenic
In biosynthesis of Coenzyme A requires
cysteine, pantothenate (vitamin B5) and
adenosine tri phosphate (ATP).
Pantothenate is found in food such as meat,
vegetables, cereal grains, legumes,
eggs and milk.
In humans and most living organism
pantothenate is an essential vitamin that
has a variety of functions.
In all living organism Coenzyme A is
synthesized in five step process that
requires for molecule of adenosine tri
phosphate(ATP) and cysteine.
Coenzyme A is produced commercially via
extraction from yeast, however this is an
inefficient process (yields approximately
25 mg/kg) resulting in an expensive product.
Various ways of producing CoA synthetically,
or semi-synthetically have been investigated
although none are currently operating at an
Fatty acid synthesis-coenzyme A is, in
chemical terms, a thiol, it can react
with carboxylic acids to form thioesters, thus
functioning as an acyl group carrier. It assists
in transferring fatty acids from
the cytoplasm to mitochondria. A molecule of
coenzyme A carrying an acyl group is also
referred to as acyl-CoA . When it is not
attached to an acyl group, it is usually
referred to as 'CoASH' or 'HSCoA'. This
process facilitates the production of fatty
acids in cells, which are essential in cell
Energy production-Coenzyme A is one of five crucial coenzymes that are necessary in the
reaction mechanism of the citric acid cycle. Its acetyl-coenzyme A form is the primary input
in the citric acid cycle and is obtained from glycolysis, amino acid metabolism, and fatty acid
beta oxidation. This process is the body's primary catabolic pathway and is essential in
breaking down the building blocks of the cell such as carbohydrates, amino acids, and lipids.
Regulation-When there is excess glucose, coenzyme A is used in the cytosol for synthesis of
fatty acids. This process is implemented by regulation of acetyl-CoA carboxylase, which
catalyses the committed step in fatty acid synthesis.
During cell starvation, coenzyme A is synthesized and transports fatty acids in the
cytosol to the mitochondria. Here, acetyl-CoA is generated for oxidation and energy
production. In the citric acid cycle, coenzyme A works as an allosteric regulator in the
stimulation of the enzyme pyruvate dehydrogenase.
Some of the sources that CoA comes from and uses in the cell.
Principle of Biochemistry, A.L.Lehninger, Worth
Bioorganic, Bioinorganic and Supramolecular
Chemistry PS KALSI, J.P.KALSI.