Glycoproteins and proteoglycans play important roles in the structure and function of cells. Glycoproteins are proteins that have carbohydrates attached, and are found on cell surfaces and in extracellular fluids. They are involved in cell recognition and adhesion. Proteoglycans are proteins with long chains of glycosaminoglycans attached. They are major components of extracellular matrices. Blood typing determines blood group based on antigens on red blood cells. Carbohydrates like glycogen and starch are stored fuels, while metabolic pathways like glycolysis break down and use carbohydrates for energy. Amino acids are the building blocks of proteins and have common structures like carbon and amino/carboxyl groups and variable R

1. BIOCHEMISTRY
PRESENTATION BY,
K.GOKILA
MSFBI1802

2. TOPICS
Glycoprotein.
proteoglycans and blood grouping.
Storage and metabolism of
carbohydrates.
Structure and classification amino
acids.

3. GLYCOPROTEIN:
 Proteins are found floating in or around the
membrane of cells. They move and can interact
with the cell's environment. Glyco is the word
derived from GREEK word.
 Glyco is a prefix in science that means 'sugar.'
Glycoprotein are simply proteins with a sugar
attached to them.
 The sugars can be attached to a protein in two
locations in the cell, the endoplasmic reticulum,
which produces N-linked sugars, and the Golgi
apparatus, which produces O-linked sugars.

4.  The N-linked glycoprotein's have a sugar attached to a
nitrogen atom, and O-linked glycoprotein's have a sugar
attached to an oxygen atom.
 The different structure of N- and O-linked sugars give
them different functions. Glycoprotein's are always
found on the outside of the plasma membrane, with the
sugar facing out.
Functions and protection:
Glycoprotein's are involved in nearly every process in
cells! They have diverse functions such as in our immune
system, protection of our body, communication between
cells, and our reproductive systems.

5.  Glycoprotein's are also important for red blood cells.
Blood type refers to the type of glycoprotein on our red
blood cells. If you have type A blood, you have A
antigens, or A glycoprotein's, on your red blood cells.
 This helps the body to identify that your blood is part of
you and tells it not to attack it. Glycoprotein's also help
to stimulate the process of coagulation of platelets to clot
blood when you get cut.
 People who are missing important proteins on platelets
can't clot their blood and have a disease called
hemophilia, where any cut continues to bleed
indefinitely.

6.  Many organs in your body need to secrete mucus to function
properly. Examples include your stomach, small intestine, and
airways in the lungs. Cells lining these body cavities secrete, or
send out, glycoprotein's.
 The sugars mixed with water in your body create a smooth
mucus. In the stomach, this mucus helps protect your stomach
lining from the harsh acids needed to digest food. In the lungs,
the mucus helps to trap bacteria.
 Glycoprotein's are also involved in keeping our skin healthy.
Glycoprotein's are on the surface of skin cells, called epithelial
cells.
 These help to attach our skin cells to each other, forming a tough
barrier to protect our body. Cadherins are an example of a
glycoprotein that helps our skin hold together.

10. PROTEOGLYCANS AND BLOOD GROUPING.
 Proteoglycans are proteins that are covalently
bonded at multiple sites along the protein chain to a
class of polysaccharides, known as
glycosaminoglycans.
 Glycosaminoglycans constitute approximately 95%
of the mass of proteoglycans by weight, which
results in proteoglycans bearing a resemblance
more to polysaccharides than to proteins.
 The physiological properties of proteoglycans are a
function of the particular glycosaminoglycans
present.Examples of common glycosaminoglycans
are chondroitin 6-sulfate, keratan sulfate, heparin,
dermatan sulfate, and hyaluronate.

11. Proteoglycans (mucoproteins) are formed of glycosaminoglycans
(GAGs) covalently attached to the core proteins. They are found
in all connective tissues, extracellular matrix (ECM) and on the
surfaces of many cell types.
A glycoprotein is a compound containing carbohydrate (or
glycan) covalently linked to protein. The carbohydrate may be in
the form of a monosaccharide, disaccharide(s). ... Proteoglycans
are a subclass of glycoproteins in which the carbohydrate units
are polysaccharides that contain amino sugars.
Two main classes of extracellular macromolecules make up the
matrix: (1) polysaccharide chains of the class called
glycosaminoglycans (GAGs), which are usually found covalently
linked to protein in the form of proteoglycans, and (2) fibrous
proteins, including collagen, elastin, fibronectin, and laminin,
which have to make up glycoprotein.

15.  Any classes of protein
which have
carbohydrates groups
attaches to the
polypeptide chain.
 Non protein content is
10 to 15 percent by
weight.
 Attached to protein
form glycoprotein.
 Mainly occur in cell
membrane.
 A compound consisting of a
protein bonded to
glycosaminoglycan groups,
present especially in
connective tissue.
 Non protein content is 50
to 60 percent by weight.
 Attached to protein form
proteoglycan.
 Mainly occur in connective
tissues.
GLYCOPROTEIN PROTEOGLYCAN

16. BLOOD GROUPING
Principle:
 The ABO and Rh blood grouping system is based on
agglutination reaction. When red blood cells carrying
one or both the antigens are exposed to the
corresponding antibodies they interact with each other to
form visible agglutination or clumping.
 The ABO blood group system is used to determine the
different types of antigens in the red blood cells and
antibodies in the plasma. ... Having none of these A/B
antigens means that they can be donated to a person with any
ABO blood type. Some red blood cells have the Rh factor,
which is also called RhD antigen.

17. Overview
 Blood typing is a test that determines a person’s blood type.
The test is essential if you need a blood transfusion or are
planning to donate blood. Not all blood types are compatible,
so it’s important to know your blood group. Receiving blood
that’s incompatible with your blood type could trigger a
dangerous immune response.
The blood types:
 The ABO blood typing system groups your blood into
one of four categories:
 Type A has the A antigen.
 Type B has the B antigen.
 Type AB has both A and B antigens.
 Type O has neither A nor B antigens.

19. In other words, donations work as follows:
 O: Type O individuals can donate blood to anyone, because
their blood has no antigens. However, they can only receive
blood from other type O individuals (because blood with any
antigens is seen as foreign).
 A: Type A individuals can donate to other type A individuals
and type AB individuals. Type A individuals can receive blood
only from other type A individuals and type O individuals.
 B: Type B individuals can donate blood to other B individuals
and AB individuals. Type B individuals can receive blood only
from type B individuals and type O individuals.
 AB: Type AB individuals can give blood only to other AB
individuals, but can receive blood of any type.

20. Why blood typing is done:
 Blood typing is done prior to a blood transfusion or
when classifying a person’s blood for donation. Blood
typing is a fast and easy way to ensure that you
receive the right kind of blood during surgery or after
an injury.
 If you’re given incompatible blood, it can lead to
blood clumping, or agglutination, which can be fatal.
 Blood typing is especially important for pregnant
women. If the mother is Rh-negative and the father is
Rh-positive, the child will likely be Rh-positive.

21.  In these cases, the mother needs to receive a drug called
RhoGAM. This drug will keep her body from forming
antibodies that may attack the baby’s blood cells if their blood
becomes mixed, which often happens during pregnancy.
The risks of blood typing:
 bleeding under the skin (hematoma)
 fainting or feeling lightheaded
 infection at the puncture site
 excessive bleeding

23. STORAGE OF CARBOHYDRATES:
 Polysaccharides are synthesized by plants, animals, and
humans to be stored for food, structural support, or
metabolized for energy.
 Glycogen: Glycogen is the storage form of glucose in animals
and humans which is analogous to the starch in plants.
Glycogen is synthesized and stored mainly in the liver and the
muscles.
 Glycogen is the storage form of glucose in animals and
humans which is analogous to the starch in plants. Glycogen is
synthesized and stored mainly in the liver and the muscles.

24.  Plants make starch and cellulose through the photosynthesis
processes. Animals and human in turn eat plant materials and
products. Digestion is a process of hydrolysis where the starch
is broken ultimately into the various monosaccharides.
 A major product is of course glucose which can be used
immediately for metabolism to make energy. The glucose that
is not used immediately is converted in the liver and muscles
into glycogen for storage by the process of glycogenesis. Any
glucose in excess of the needs for energy and storage as
glycogen is converted to fat.

27.  Metabolism of carbohydrates:
Carbohydrate Metabolism. Carbohydrate metabolism is a
fundamental biochemical process that ensures a constant
supply of energy to living cells. The most important
carbohydrate is glucose, which can be broken down via
glycolysis, enter into the Kreb's cycle and oxidative
phosphorylation to generate ATP.
Carbohydrate metabolism begins with digestion in the
small intestine where monosaccharides are absorbed into the
blood stream. Blood sugar concentrations are controlled by
three hormones: insulin, glucagon, and epinephrine. If the
concentration of glucose in the blood is too high, insulin is
secreted by the pancreas.

28.  Most cells are capable of regulating their carbohydrate
metabolism based on their current energy requirements. ...
The important metabolites involved in regulation of
carbohydrate metabolism include ATP, NADH, glucose-6-
phosphate, citrate, and fructose-2,6-bisphosphate.
The metabolic products of carbohydrates and the fatty acids
derived from triglycerides are carbon dioxide, water and an
energy-storing molecule called ATP.
Metabolism is the process your body uses to make energy
from the food you eat. ... If you have a metabolic disorder,
something goes wrong with this process. Carbohydrate
metabolism disorders are a group of metabolic disorders.
Normally your enzymes break carbohydrates down into
glucose (a type of sugar).

30.  Gluconeogenesis pathway with key molecules and enzymes.
Many steps are the opposite of those found in the glycolysis.
Gluconeogenesis (abbreviated GNG) is a metabolic pathway
that results in the generation of glucose from non-
carbohydrate carbon substrates such as lactate, glycerol, and
glucogenic amino acids.
 It is one of the two main mechanisms humans and many
other animals use to keep blood glucose levels from dropping
too low (hypoglycemia). The other means of maintaining
blood glucose levels is through the degradation of glycogen
(glycogenolysis).
GLUCONEOGENESIS:

31.  It is one of the two main mechanisms humans and many other
animals use to keep blood glucose levels from dropping too
low (hypoglycemia). The other means of maintaining blood
glucose levels is through the degradation of glycogen
(glycogenolysis).
 Gluconeogenesis is a ubiquitous process, present in plants,
animals, fungi, bacteria, and other microorganisms. In animals,
gluconeogenesis takes place mainly in the liver and, to a lesser
extent, in the cortex of kidneys.
 This process occurs during periods of fasting, starvation, low-
carbohydrate diets, or intense exercise and is highly
endergonic.

32.  For example, the pathway leading from phosphoenolpyruvate
to glucose-6-phosphate requires 6 molecules of ATP.
Gluconeogenesis is often associated with ketosis.
Gluconeogenesis is also a target of therapy for type II diabetes,
such as metformin, which inhibits glucose formation and
stimulates glucose uptake by cells.
 Gluconeogenesis is not the reversal of the glycolysis, but the
generation of glucose from non-carbohydrate precursors (like
odd chain fatty acids and proteins). The reason why we have
this process is because some organs and tissues can only use
glucose as their energy source.

33.  It has the opposite effect as that of insulin. Adrenal gland
cortisol: Cortisol is a steroid hormone produced by the
adrenal gland and promotes gluconeogenesis. It is released in
response to stress and low blood glucose levels. It functions
to increase blood glucose through gluconeogenesis.
 Gluconeogenesis occurs in the liver and kidneys.
Gluconeogenesis supplies the needs for plasma glucose
between meals. Gluconeogenesis is stimulated by the
diabetogenic hormones (glucagon, growth hormone,
epinephrine, and cortisol). Gluconeogenic substrates include
glycerol, lactate, propionate, and certain amino acids.

34. Carbohydrate metabolism. ... In aerobic respiration, the
main form of cellular respiration used by humans,
glucose and oxygen are metabolized to release energy,
with carbon dioxide and water as byproducts. Most of the
fructose and galactose travel to the liver, where they can
be converted to glucose.
The energy released is used to power the cells and
systems that make up your body. Excess or unutilized
energy is stored as fat or glycogen for later use.
Carbohydrate metabolism begins in the mouth, where the
enzyme salivary amylase begins to break down complex
sugars into monosaccharides.

36.  Structure of amino acid:
Amino acid, any of a group of organic molecules that consist of
a basic amino group (―NH2), an acidic carboxyl group
(―COOH), and an organic R group (or side chain) that is
unique to each amino acid. The term amino acid is short for α-
amino [alpha-amino] carboxylic acid.
Each molecule contains a central carbon (C) atom, called
the α-carbon, to which both an amino and a carboxyl
group are attached. The remaining two bonds of the α-
carbon atom are generally satisfied by a hydrogen (H)
atom and the R group.

37. Chemically speaking, an amino acid is a carboxylic acid which has
an amine group attached to it. The general linear formula of an
amino acid is R-CH(NH2)-COOH.
Amino acids bond together to make long chains. Those long chains
of amino acids are also called proteins. Essential Amino Acids:
Histidine, Isoleucine, Leucine, Lysine, Methionine,
Phenylalanine, Threonine, Tryptophan, and Valine.
Nonessential Amino Acids: Alanine, Asparagine, Aspartic Acid,
Glutamic Acid.
The key elements of an amino acid are carbon (C), hydrogen (H),
oxygen (O), and nitrogen (N), although other elements are found
in the side chains of certain amino acids

40. There are actually thousands of amino acids occurring in nature.
But only about 20 amino acids form a part of the proteins in the
human body. These twenty acids will be our focus here. Although
all these have varied structures, the basic structure of amino acid
remains uniform.
All amino acids contain a carbon atom in the middle of the
molecule, the alpha-carbon .This atom is surrounded by three
chemical groups.
One is an amine group -NH2.The second one is a carboxyl group –
OOOH
The third group is denoted by R. This is the variable radical group
and is different for every amino acid. This R group makes the
amino acid unique.

41. Classification of Amino Acids:
Amino Acid can be classified based on their structure and the
structure of their side chains i.e. the R chains. Now two basic
subcategories are:
1] Non-Polar Amino Acids:
These are also known as Hydrophobic. The R group can be either
of Alkyl groups (with an alkyl chain) or Aromatic groups. The
acids falling in this group are stated below. Numbers one to seven
are Alkyl and the last two are aromatic.

42. Glycine (H)
Alanine (CH3)
Valine ( CH (CH3)2 )
Methionine ( CH2CH2SCH3 )
Leucine ( CH2CH(CH3)2 )
Isoleucine ( -CH(CH3)CH2CH3 )
Proline (special structure)
Phenylalanine
Tryptophan

43. 2] Polar Amino Acids:
If the side chains of amino acid contain different polar groups like
amines, alcohols or acids they are polar in nature. These are also
known as Hydrophilic Acids. These are further divided into three
further categories.
a) Acidic: If the side chain contains an extra element of carboxylic
acid component these are acid-polar amino acids. They tend to
donate their hydrogen atom. These are:
Aspartic Acid ( CH2COOH)
Glutamic Acid ( CH2CH2COOH )

44. b) Basic: These have an extra nitrogen group that tend to attract a
hydrogen atom. The three basic polar amino acids are.
Histidine
Lysine ( CH2(CH2)2NH2 )
Arginine
c) Neutral: These are neither acidic nor basic. They have an equal
number of amino and carboxyl groups. Also, they have at least one
hydrogen component connected to electronegative atoms. Some of
these neutral acids are
Serine ( CH2OH )
Threonine ( CH(OH)CH3 )
Asparagine ( CH2OHNH2 )
Glutamine ( CH2CH2CONH2 )
Cysteine ( CH2SH )
Tyrosine

45. Amino acid can also be classified on the basis of their need to the
human body and their availability in the human body.
1] Essential Amino Acids:
These are the acids that cannot be synthesized in our bodies. We
must rely on food sources to obtain these amino acids. They are:
Leucine
Isoleucine
Lysine
Theorine
Methionine
Phenylalanine
Valine
Tryptophan
Histidine (conditionally essential)

46. 2] Non-Essential
These acids are synthesized in our bodies itself and we need not
rely on outside sources for them. They are either produced in our
bodies or obtained from protein breakdowns.
Properties of Amino Acids:
Each amino acid has both an acidic and basic group as you can see
from its structure. This is the reason they behave like salts.
Any amino acid in the dry state is in crystalline form. They exist
as a dipolar ion. The COOH group exists as an anion. And the
NH2 group exists as a cation. This dipolar ion has a special name
“Zwitter ions’.

47. •In aqueous solution, alpha amino acids exist in equilibrium
between a cationic form, an anionic form and dipolar ion.
•The Isoelectric point is the pH point at which the concentration of
zwitter ions is the highest ad the concentration of cationic and
anionic form is equal. This point is definite for every α-amino
acid.
•They are generally water soluble and also have high melting
points.