Biotechnology

Biotechnology is the use of living systems and organisms to develop or make useful products, or

"any technological application that uses biological systems, living organisms or derivatives

thereof, to make or modify products or processes for specific use" (UN Convention on Biological

Diversity, Art. 2).

Biotechnology has applications in four major industrial areas, including health care (medical), crop

production and agriculture, non-food (industrial) uses of crops and other products (e.g.

biodegradable plastics, vegetable oil, biofuels), and environmental uses.

Proteins

Proteins are large biological molecules, or macromolecules, consisting of one or more long chains

of amino acid residues.

Of all the molecules encountered in living organisms, proteins have the most diverse functions,

as the following list suggests.

1. Catalysis. Catalytic proteins called the enzymes accelerate thousands of biochemical

reactions in such processes as digestion, energy capture, and biosynthesis.

2. Structure. Structural proteins often have very specialized properties.

3. Movement. Proteins are involved in all cell movements.

4. Defense. A wide variety of proteins are protective.

5. Regulation. Binding a hormone molecule or a growth factor to cognate receptors on its

target cell changes cellular function.

6. Transport. Many proteins function as carriers of molecules or ions across membranes or

between cells.

7. Storage. Certain proteins serve as a reservoir of essential nutrients.

8. Stress response. The capacity of living organisms to survive a variety of abiotic stresses

is mediated by certain proteins.

Amino Acids

Proteins can be distinguished based on their number of amino acids (called amino acid

residues), their overall amino acyl composition, and their amino acid sequence. Molecules with

molecular weights ranging from several thousand to several million Daltons are called

polypeptides. Those with low molecular weights, typically consisting of fewer than 50 amino

acids, are called peptides.

Plants and bacteria can synthesize all 20 of the amino acids. Whereas, humans cannot synthesize

9 of them. These nine amino acids must come from our diets and are called essential amino acids.

The essential amino acids are: Histidine, Isoleucine, Leucine, Lysine, Methionine,

Phenylalanine, Threonine, Tryptophan and Valine.

The 20 Amino Acids

Carbohydrates

A carbohydrate is a large biological molecule, or macromolecule, consisting of carbon (C),

hydrogen (H), and oxygen (O) atoms, usually with a hydrogen: oxygen atom ratio of 2:1 (as in

water); in other words, with the empirical formula Cm(H2O)n (where m could be different from n).

Carbohydrates are technically hydrates of carbon; structurally it is more accurate to view them as

polyhydroxy aldehydes and ketones.

The term is most common in biochemistry, where it is a synonym of saccharide. The

carbohydrates (saccharides) are divided into four chemical groups:

monosaccharides

disaccharides

oligosaccharides

polysaccharides.

Like

most classes of biological molecules, carbohydrates occur as both monomers and polymers.

Small carbohydrates are called sugars, which commonly include monosaccharides (single

sugars) and some disaccharides (two sugars linked together). Larger carbohydrates are called

polysaccharides (many sugars linked together).

Monosaccharides

These are the only sugars that can be absorbed and utilized by the body. Disaccharides and

polysaccharides must be ultimately broken down into monosaccharides in the digestive process

known as hydrolysis. Only then can they be utilized by the body. Three monosaccharides are

particularly important in the study of nutritional science: glucose, fructose and galactose.

1. Glucose (also known as dextrose or grape sugar)

This monosaccharide is the most important carbohydrate in

human nutrition because it is the one that the body fuses directly

to supply its energy needs. Glucose is formed from the hydrolysis

of di- and polysaccharides, including starch, dextrin, maltose,

sucrose and lactose; from the monosaccharide fructose largely during absorption; and from both

fructose and galactose in the liver during metabolism. Glucose is the carbohydrate found in the

bloodstream, and it provides an immediate source of energy for the body’s cells and tissues.

Glucose is also formed when stored body carbohydrate (glycogen) is broken down for use.

2. Fructose (also known as levulose or fruit sugar)

Fructose, a monosaccharide, is very similar to another

monosaccharide, galactose. These two simple sugars share the

same chemical formula; however, the arrangements of their

chemical groups along the chemical chain differ. Fructose is the

sweetest of all the sugars and is found in fruits, vegetables and the nectar of flowers, as well as

in the unwholesome (to humans) sweeteners, molasses and honey.

3. Galactose

Galactose differs from the other simple sugars, glucose and fructose, in

that it does not occur free in nature. It is produced in the body in the

digestion of lactose, a disaccharide.

Disaccharides

Disaccharide, also called Double Sugar, any substance that is composed of two molecules of

simple sugars (monosaccharides) linked to each other.

Disaccharides are formed when two monosaccharides are joined together and a molecule of

water is removed, a process known as dehydration reaction. For example; milk sugar (lactose) is

made from glucose and galactose whereas the sugar from sugar cane and sugar beets (sucrose)

is made from glucose and fructose.

1. Sucrose

The disaccharide, sucrose, consists of one molecule of each

of two monosaccharides—glucose and fructose. Sucrose is

found in fruits and vege ables and is particularly plentiful in

sugar beets (roots) and sugarcane (a grass). Refined white

and brown sugars are close to 100% sucrose because

almost everything else (including the other kinds of sugars present, the vitamins, the minerals and

the proteins) have been removed in the refining process.

2. Maltose (also known as malt sugar)

This disaccharide, unlike sucrose, is not consumed

in large amounts in the average American diet. It is

found in malted cereals, malted mi lks and sprouted

grains.

Maltose occurs in the body as an intermediate

product of starch digestion. (Starch is a

polysaccharide.) When maltose is hydrolyzed, it

yields two molecules of glucose.

3. Lactose (also known as milk sugar)

This disaccharide is found only in milk. Human milk

contains about 4.8 g per 100 ml and cow’s milk

contains approxim ately 6.8 g per 100 ml. When

lactose is hydrolyzed it yields one unit of the

monosaccharide glucose and one unit of the

monosaccharide galactose.

Polysaccharides

Polysaccharides are polymeric carbohydrate structures, formed of repeating units (either mono-

or di-saccharides) joined together by glycosidic bonds. These structures are often linear, but may

contain various degrees of branching.

Polysaccharides have a general formula of Cx(H2O)y where x is usually a large number between

200 and 2500. Considering that the repeating units in the polymer backbone are often six-carbon

monosaccharides, the general formula can also be represented as (C6H10O5)n where 40 ≤ n ≤

3000.

1. Starch

Starch is abundant in the plant world and is

found in granular form in the cells of plants.

Starch granules can be seen under a microsc

ope and they differ in size, shape and

markings in various plants.

2. Dextrin

There are several “varieties” of this

polysaccharide. Dextrins are most commonly

consumed in cooked starch foods, as they are

obtained from starch by the action of heat.

Dextrins are intermediary products of starch

digestion, also, and are formed by the action of amylases on starches. They render the disaccha

ride maltose on hydrolysis.

3. Glycogen

Glycogen is the reserve carbohydrate in humans. It

is to animals as starch is to plants. Glycogen is very

similar to amylopectin, having a high molecular

weight and branched-chain structures made up of

thousands of glucose molecules.

The main difference between glycogen and

amylopectin is that glycogen has more and shorter branches, resulting in a more compact,

bushlike molecule with greater solubility and lower viscosity (less stickiness or gumminess).

4. Cellulose

Like starch and glycogen, cellulose is composed of th

ousands of glucose molecules. It comprises over

50% of the carbon in vegetation and is the structural

constituent of the cell walls of plants.

Cellulose is, therefore, the most abundant naturally-

occurring organic substance. It is characterized by its insolubility, its chemical inertness and its

physical rigidity.

Lipids, Fats and Steroids

Lipids

Lipids are group of naturally occurring compounds, which have in common a ready solubility in

such organic solvents. They include a diverse range of compounds, like fatty acids and their

derivatives, carotenoids, terpenes and terpenoids, steroids and bile acids.

Table 1. Classification of Lipids

Lipids Description Types/

Classification

Examples /

Derivatives

Fatty Acids

-compounds

synthesized in

nature

via condensation

of malonyl

coenzyme

-usually contain

even numbers of

carbon atoms in

straight chains

(commonly C14

to C24)

1.

2.

3. 1. Saturated Fatty

Acids - triglycerides

4. contain the

maximum possible

amount of

hydrogens

5.

2. Unsaturated fatty

Acids - they’re not

bonded to as many

6. hydrogens as they

could if they weren’t

Lauric Acid

Myristic Acid

Palmitic Acid

Stearic Acid

Linoleic Acid

Oleic Acid

Capric Acid

- -Fatty acids are

usually derived

from triglycerides

or phospholipids

-When they are

not attached to

other molecules,

they are known

as "free" fatty

acids.

double bonded to

each other

Terpenes and

Terpenoids

- group of

molecules whose

structure is based

on a various

but definite

number of

isoprene units

-The difference

between terpenes

and terpenoids is

that terpenes are

hydrocarbons,

whereas

terpenoids

contain

additional functio

nal groups

Vitamin A

Aroma used

in Perfumery

Primary

constituents of

essential oils

from plants

and flowers

Natural flavor

additives for

food

Steroids

-type of organic

compound that

contains a

characteristic

arrangement of

four cycloalkane r

ings joined to one

another

Sex

hormones,

Testosterone

and Estradiol

Adrencortical

hormones

D vitamins

Bile acids

Cardiac

Poisons

Cholesterol

-lipid with a

unique structure

consisting of four

linked

hydrocarbon rings

forming the bulky

steroid structure

-known as a

"sterol" because it

is made out of

an alcohol and

steroid.

------------------------ ------------------

Sex Hormones

(Steroid Hormones)

-steroid hormones

are all derived

from cholesterol

- they all contain

the same

cyclopentanophe

nanthrene ring

Important

mammalian

hormones are

shown below

------------------

and atomic

numbering

system as

cholesterol

- Steroid

hormones with 21

carbon atoms are

known

systematically as

pregnanes,

whereas those

containing 19 and

18 carbon atoms

are known as

androstanes and

estranes,

respectively.

Table 2. Important Mammalian Hormones

Question

1. Protein can be distinguished based on its ________________.

a. Amino Acid

b. Amino Acid Residues

c. peptides bonds

d. number of carbons

Answer: B. Amino Acid Residues - can be distinguished based on their number of amino acids,

their overall amino acyl composition, and their amino acid sequence.

2. Polysaccharides can be broken down into monosaccharaides by means of

______________.

a. Digestion and Hydrolysis

b. Heating

c. Enzymatic Hydrolysis

d. Hydrolysis

Answer: D. Hydrolysis – used to degrade the glucose from the cellulosic structure of a

biomass.

3. Produced in the body by means of digestion of lactose.

a. Fructose

b. Galactose

c. Glucose

d. Lactose

Answer: B. Galactose - When lactose is hydrolyzed it yields one unit of the monosaccharide

glucose and one unit of the monosaccharide galactose.

4. Also known as Malt Sugar

a. Maltose

b. Lactose

c. Fructose

d. Dextrin

Answer: A. Maltose - Maltose occurs in the body as an intermediate product of starch

digestion.

5. ___________: Animals; Starch: Plants

a. Dextrin

b. Glycogen

c. Cellulose

d. Glucose

Answer: B. Glycogen - Glycogen is the reserve carbohydrate in humans. It is to animals as

starch is to plants. Glycogen is very similar to amylopectin, having a high molecular weight

and branched-chain structures made up of thousands of glucose molecules.

6. The following are important derivatives of steroid except:

a. Vitamin A

b. Vitamin D

c. Bile Acids

d. None

Answer: A. Vitamin A – Vitamin D, Bile Acids are some important derivatives from steroid,

Vitamin A is not included.

7. Lipid with a unique structure consisting four linked hydrocarbon rings forming the bulky

steroid structure

a. Cardiac Poisons

b. Bile Acid

c. Cholesterol

d. Estradiol

Answer: C. Cholesterol – Based on the chemical formula –

8. Most commonly consumed in cooked starch foods.

a. Dextrins

b. Glycogen

c. Glucose

d. Estrogen

Answer: A. Dextrins – Dextrins are most commonly consumed in cooked starch foods, as they

are obtained from starch by the action of heat.

9. Polysaccharides have a general formula of ________________.

a. Cy(H2O)x

b. Cy2(H2O)x

2

c. Cx(H2O)y

d. Cy2(H2O)x

2

Answer: C. Cx(H2O)y – Polysaccharides have a general formula of Cx(H2O)y where x is usually a

large number between 200 and 2500

10. Milk: lactose; Malted Cereals: ____________.

a. Maltose

b. Glucose

c. Sucrose

d. Fructose

Answer: A. Maltose – This disaccharide, unlike sucrose, is not consumed in large amounts in

the average American diet. It is found in malted cereals, malted mi lks and sprouted grains.

11. The sweetest of all the sugars and is found in fruits, vegetables and the nectar of flowers, as

well as in the unwholesome (to humans) sweeteners, molasses and honey.

a. Maltose

b. Glucose

c. Sucrose

d. Fructose

Answer: D. Fructose – Fructose, a monosaccharide, is very similar to another monosaccharide,

galactose. These two simple sugars share the same chemical formula; however, the

arrangements of their chemical groups along the chemical chain differ.

References:

Amino Acids, Peptides and Proteins. Date Retrieved: July 23, 2014

Biotechnology. Date Retrieved: July 23, 2014 from http://en.wikipedia.org/ wiki/ Biotechnology

Carbohydrates. Date Retrieved: July 23, 2014 from http://www.harpercollege.edu/tm-

ps/chm/100/dgodambe/thedisk/carbo/yback2.htm

Introduction: Steroid Hormones. Date Retrieved: July 23, 2014 http://themedical

biochemistrypage.org/steroid-hormones.php

Lipid. Date Retrieved: July 23, 2014 from http://biology.about.com/od/molecular

biology/ss/lipids.htm

Terpene. Date Retrieved: July 23, 2014 from http://en.wikipedia.org/wiki/Terpene

Polysaccharides. Date Retrieved: July 23, 2014 from http://en.wikipedia.org/wiki

/Polysaccharide

Saccharides. Date Retrieved: July 23, 2014 from