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Structure & Classification of Proteins

Dr. Bibi Kulsoom

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http://www.picturesof.net/pages/100103-180324-843042.html

Other dry

elements

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http://www.indiabix.com/_files/images/data-interpretation/pie-charts/15-2-11-1.png

Proteins

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Proteins: Amino Acids

Hydrocarbon chainhttp://www.whitetigernaturalmedicine.com/wp-content/uploads/2012/02/amino-acid-structure.jpg

Hydrolysis by

digestive enzymes

Protein molecule

Amino acids

One Amino acid structure

http://www.hardbodysuccessblog.com/.a/6a00e00995147488330115704e4379970c-pi

Peptide bond

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Essential amino acids1. Arginine (partially essential)

2. Histidine

3. Isoleucine

4. Leucine

5. Lysine

6. Methinine

7. Phenylalanine

8. Threonine

9. Tryptophan

10.Valine

Non-Essential amino acids1. Alanine

2. Aspartic acid

3. Asparagine

4. Cysteine

5. Glutamic acid

6. Glutamine

7. Glycine

8. Proline

9. Serine

10.Tyrosine

Proteins are Composed :of 20 Amino Acids

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Classification is based on

• Composition

• Shape

• Function

Proteins & their Classification

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http://njscuba.net/zzz_artifacts/protein_2.gif

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1. Simple proteins:

A protein that contains amino acids only.

Examples: albumin, globulins & histones.

2. Conjugated Proteins:

A protein that have some non-protein moiety in its structure along

with protein part.

3. Derived proteins:

Proteins derived from simple and conjugated proteins by physical

or chemical treatment. Examples: peptones peptides and

denatured proteins.

Classification Based on Composition

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Conjugated Proteins

Nucleoproteins

Glycoproteins

Mucoproteins

Lipoproteins

Phosphoproteins

Chromoproteins

Metalloproteins7

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Nucleoproteins

http://1.bp.blogspot.com/_Ik_ovkt6ICg/TNoWaLBLKXI/AAAAAAAAAIk/

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Proteins examples:

Histones, telomerase.

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Glycoproteins

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Proteins examples:

Glycoproteins of cell membrane, Follicle-stimulating hormone

(FSH), Luteinizing hormone (LH).

http://designanduniverse.com/articles/images/cell/cell_membrane.jpg

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Lipoproteins

http://www.scientificpsychic.com/health/lipoproteins-LDL-HDL.html

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Proteins examples:

Low density lipoprotein (LDL), high density lipoprotein (HDL).

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Phosphoproteins

Enzyme A

Inactive

Inactive

Active

Active

Enzyme A P

Enzyme B PEnzyme B

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Proteins examples:

Enzymes (protein in nature) are phosphorylated temporarily for their

regulation.

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Chromoproteins

Cytochromes P450

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Proteins examples:

Hemoglobin, cytochromes (enzymes).

http://chemistry.wiki.elanco.net/file/view/hemoglobin.jpg/120238735/hemoglobin.jpg

http://www.presentermedia.com/files/clipart/00001000/1744/blood_cells_pc_md_wm.jpg

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Metalloproteins

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Proteins examples:

Hemoglobin, Ceruloplasmin (protein that stores and

transports copper)

Ceruloplasmin

Ceruloplasmin

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Proteins

Globular Proteins

Albumin

Globulins

Glutelins

Prolamines

Histones

Globins

Protamines

Fibrous Proteins or Scleroproteins

Collagens

Elastins

Keratins

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Based on Shape

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Globular ProteinsHemoglobin and myoglobin are examples of globular proteins.

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Fibrous Proteins or Scleroproteins

-keratin

-keratin

Collagen fiber

Collagen, keratin and elastin are examples of fibrous proteins.

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Classification based on Function

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Proteins gives our cells shape,

strength as well as enable movements.

Proteins examples:

keratin, collagen, elastin.

Structure Examples:

Hair, wool, nails, horns,

hoofs, tendons, cartilage.

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Structural Proteins

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Contractile Proteins

Proteins examples:

Actin & myosin

Location in body:

Contracting fibers in muscle.

http://www.performance-edu.com/Insider%20News/Volume%202/Images/small%20animated%20sliding%20filament.gif

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http://www.123rf.com/photo_7661491_young-man-running-in-forest.html

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Storage Proteins

Proteins examples:

• Different for different sustances.

• Ferritin (Stores iron in spleen)

• legumes and beans in plants

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Protein examples:

• hemoglobin (Carries oxygen

in blood)

• serum albumin (Carries fatty

acids in blood)

Transport Proteins

http://blu.stb.s-msn.com/i/44/78A5F212E699FFFB5345C2214AE50.jpg

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Proteins as Enzymes

• Many proteins act as biological

catalysts or enzymes.

• Thousands of different enzymes

exist in the body.

• Examples: catalase, amylase,

trypsin, lipase.

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http://www.biology.arizona.edu/immunology/tutorials/antibody/graphics/antibody.gif

Bacte

rium

Antibody

Antibody

Proteins examples:

Gamma globulins

• when a pathogen enters the

body, the immune system

produces antibodies against it

that fight against the invader.http://www.microbiologyonline.org.uk/about-microbiology/microbes-and-the-human-body

Immunological Proteins

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Proteins as Buffers

Example:

Plasma proteins and intracellular

preoteins.

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http://human-physiology---ashley-vg.wikispaces.com/Chemical+Aspects+of+Physiology

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Maintaining Osmotic Pressure

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Protein examples:

Albumin, globin, globulin.

Protein as Hormone

http://www.hcc.bcu.ac.uk

Hormone

Examples: Insulin, glucagon,

growth hormone etc.

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Channels: Protein pores that run like tunnels across the lipid bilayer will allow

specific materials that we need, like glucose, to slip through the membrane.

Receptors: proteins that mediate the effects of hormones in side the cell.

Protein Channels & Receptors

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Cell cytoskeletonExamples: Microfilaments, intermediate filaments & microtubules.

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Clotting Factors

Clotting proteins

activate and make

meshwork of fibrin to

stop bleeding.

Examples:

Factors I, II, III, IV, V

etc.

http://media-3.web.britannica.com/eb-media//28/98328-050-4F03CFD9.jpg

http://www.buzzle.com/img/articleImages/323361-36236-16.jpg

http://upload.wikimedia.org/wikipedia/commons/thumb/e/e6/

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Type of proteinExample Function

Structural proteins keratin, collagen Hair, wool, nails, horns, hoofs, tendons, cartilage

Contractile proteins actin, myosin  Contracting fibers in muscle

Transport proteinshemoglobinserum albumin

Carries oxygen in bloodCarries fatty acids in blood

Storage proteins ferritin Stores iron in spleen

Hormones insulin, glucagon Regulates use of blood sugar

Immunological proteins

antibodies Rid the body of foreign proteins

Enzymesamylase Promotes the break down of starch to

the simple sugar glucose.

Toxinsneurotoxin Cobra venom blocker of nerve

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