Introduction to Co-Enzymes and basically their Function in Metabolism.

2. Co-enzymes and their role in regulation
of metabolic process
To presented: Dr. Ahmad Khan
Presenter: Waqas Siddiqe
Reg No 059

3. Introduction to Co-enzymes
 Co-enzyme can be defined as :
 A non-protein organic compound that is necessary for the functioning
of an enzyme is called co-enzyme.
 “OR”
 Co-enzymes are reusable non-protein molecules that contain carbon
(organic). They bind loosely to an enzyme at the active site to help
catalyze reactions .They cannot function alone, but can be reused
several times when paired with an enzyme.
 It provides the transfer site for biochemical reactions catalyzed by an
enzyme..


4. Types of Co-enzymes
 Coenzymes can be classified into two groups depending on the
interaction with apo enzyme.
 "prosthetic group",
 The first is called a "prosthetic group", The prosthetic group remains
bonded for the enzyme during the reaction. In some cases, the
prosthetic group is covalently bound for its apo enzyme .It consists of
a coenzyme that is tightly or even covalently, and permanently bound
to a protein.
 "co substrates",
 The coenzymes of the second type-often called co-substrates are
substrates in the reactions catalyzed by enzymes. Co-substrate is
changing during the reaction and dissociating from the active center.
They are transiently bound to the protein.

5. Introduction to Co-enzymes
 Salient Features of Co-
enzymes:
 Many Co-enzymes (not all) are
vitamins or are derived from
vitamins.
 Most of them contain
adenosine monophosphate
(AMP).
 A coenzyme requires the
presence of an enzyme in order
to function. It is not active on
its own.

6. Salient Features of Co-enzymes:
 They are intermediate carriers of an atom or group of atoms, allowing
a reaction to occur.
 Coenzymes may be described as either co substrates or prosthetic
groups.
 Coenzymes are often broadly called cofactors, but they are
chemically different.
 Coenzymes are heat stable.
 They are low-molecular weight substances.
 The coenzymes combine loosely with the enzyme molecules and so,
the coenzyme can be separated easily by dialysis.
 When the reaction is completed, the coenzyme is released from the
apo-enzyme, and goes to some other reaction site.

7. Functions of Co-enzymes
 One primary function of coenzymes is to help with the production of
energy. Specifically, the coenzyme ATP is a major player in moving
energy within the cell. ATP's structure has three phosphate groups,
and when the last one is cleaved off during a process known as
hydrolysis, energy is released.
 The coenzymes or co – substrates are small type organic molecule,
non – proteinaceous, whose main function in the body is to transport
specific chemical groups between various enzymes, without forming
part of the structure of them.
 Example:
 Coenzyme A has a complex structure consisting of an adenosine
triphosphate, a pantothenic acid which is a B-vitamin and cysteamine.
The coenzyme is involved in transfer of acyl-groups.

8. Functions of Co-enzymes
 Coenzyme A derived from pantothenic acid, important in respiration
and other biochemical reactions.
 The coenzyme is essential for the biological activity of the enzyme.
 A coenzyme is a low molecular weight organic substance, without
which the enzyme cannot exhibit any reaction.
 One molecule of the coenzyme is able to convert a large number of
substrate molecules with the help of enzyme.
 Co-enzymes are considered to be secondary substrates of the
reaction.

9. Mechanism of Action of Co-enzymes
 Coenzymes bind to the enzyme
and assist in enzyme activity.
They can bind and react with
many different enzymes, so
they're not specific to a
particular enzyme. They help
enzymes change starting
elements (substrates) into their
final version (products). In
doing this, the coenzyme can
be changed and often
alternates between various
forms.

10. Mechanism of Action of Co-enzymes
 There are several ways coenzymes assist in enzyme function,
including changing their shape to activate, or turn on, enzymes, or
aiding in chemical reactions by acting as carriers of energy or
molecular groups.
 Coenzymes cannot function on their own and require the presence
of an enzyme. Some enzymes require several coenzymes and
cofactors.
 Coenzymes are responsible for filling in any gaps that are present in
proteins. Molecules will be filled into the gaps so that the catalytic
reaction can be released without coenzymes, many enzymes could not
create these catalytic reactions because there are gaps that prevent
the enzyme from bonding completely.
 Coenzymes hold an atom or group of atoms, allowing an enzyme to
work.

11. Mechanism of Action of Co-enzymes
 Some coenzymes may bind to an enzyme when needed, on a
temporary basis, while others attach permanently. The type of
attachment formed will depend on the enzyme and the coenzyme. If
the coenzyme is permanently bonded with the enzyme, it is called a
holoenzyme. Any enzyme that needs the help of a coenzyme for
metabolism but does not permanently attach with it is called an apo
enzyme.
 They are intermediate carriers of an atom or group of atoms, allowing
a reaction to occur. Coenzymes are not considered part of an enzyme's
structure. It can be considered a helper molecule for a biochemical
reaction.

12. EXAMPLES OF COENZYMES
 There are some important examples and their role in the body is given
below.
 Coenzyme A (CoA) . Responsible for transferring acyl groups
necessary for various metabolic cycles (such as the synthesis and
oxidation of fatty acids), is a free coenzyme derived from vitamin
B5. Meat, mushrooms and egg yolk are foods rich in this vitamin.

13. EXAMPLES OF COENZYMES
 Vitamin C (ascorbic acid)
 It is a sugar acid that acts as
a powerful antioxidant and whose
name comes from the disease that
causes its deficiency,
called scurvy . The synthesis of this
coenzyme is expensive and
difficult, so its intake is necessary
through the diet.
 Vitamin K
 Linked to the blood coagulation
factor, it acts as an activator of
different plasma proteins and
osteocalcina. It is achieved in
three ways: Vitamin K 1 , abundant
in any diet and of vegetable
origin; Vitamin K 2 of bacterial
origin and Vitamin K 3 of synthetic
origin.

14. EXAMPLES OF COENZYMES
 Coenzyme Q10 (ubiquinone)
 It is also known as ubidecarenone or
coenzyme Q, and is common to
almost all existing mitochondrial
cells. It is vital for aerobic cellular
respiration, generating 95% of the
energy of the human body as ATP
. It
is considered an antioxidant and is
recommended as a dietary
supplement, since in old age this
coenzyme stops being able to be
synthesized.

15. EXAMPLES OF COENZYMES
Vitamin B 6 (pyridoxine)
Water-soluble coenzyme
eliminated through urine, so it
has to be replaced through the
diet: wheat germ, cereals,
eggs, fish and vegetables,
among other foods. It
intervenes in the metabolism
of neurotransmitters and
has a prominent role in the
energy circuit.
 Coenzyme B
 It is vital in the redox
reactions proper to the
generation of methane by
microbial life.

16. Role of co-enzymes in metabolism
 Coenzymes are critical for your metabolism. Without these
substances, many of the metabolic catalysts that your body needs to
function properly cannot happen. These are organic substances that
normally include a mineral or vitamin. These substances bind with a
specific protein to build an enzyme system that is active. Coenzymes,
also called cofactors, give the added help an enzyme needs to
catalyze a reaction. Coenzymes assist in starting catalytic reactions
because the enzyme cannot do it by itself.
 Example:
 Coenzyme A (CoASH) has a clearly defined role as a cofactor for
a number of oxidative and biosynthetic reactions in intermediary
metabolism. Formation of acyl-CoA thioesters from organic carboxylic
acids activates the acid for further biotransformation reactions and
facilitates enzyme recognition.



17. Role of co-enzymes in metabolism
 Coenzyme A in Activation of Metabolic Pathways:
 The metabolic oxidation of glucose does not take place in one step. The
anaerobic breakdown of glucose requires many steps, and the complete
aerobic oxidation of glucose to carbon dioxide and water has still more
steps. One of the most important points about the multistep nature of
all metabolic processes, including the oxidation of glucose, is that the
many stages allow for efficient production and use of energy.
 The electrons produced by the oxidation of glucose are passed along to
oxygen, the ultimate electron acceptor, by intermediate electron
acceptors. Many of the intermediate stages of the oxidation of glucose
are coupled to ATP production by phosphorylation of ADP.

18. Role of co-enzymes in metabolism
Coenzymes are critical for your metabolism. Without these substances,
many of the metabolic catalysts that your body needs to function
properly cannot happen. The end result would be the death of all the
cells in your body and therefore the death of your body as well.
Coenzymes are needed for all phases of metabolism, both anabolism and
catabolism, to help assist enzymes in forming catalytic reactions, which
are necessary for life.
Summary of metabolic process:
 Metabolic pathways proceed in many stages, allowing for efficient use
of energy.
 Many coenzymes, particularly coenzyme A (CoA) play a crucial role in
metabolism.


19. Importance of metabolic co-enzyme supplements
When should you take metabolic enzymes supplements?
 Maintaining healthy enzyme levels in the body is paramount and doing
so may require you to regularly take metabolic enzymes supplements.
Here are a few things that may lower your body’s enzyme-count:
 Exposure to pesticides.
 Excessive intake of heated foods.
 Pancreas-related conditions, such as pancreatitis, pancreatic cancer,
and cystic fibrosis.
 There are over 30 trillion cells in the body, and metabolic enzymes
control the chemical reactions in each one of them. It goes to show
how vital they are to the human body; its survival and nourishment.