SlideShare a Scribd company logo
Amino Acids and Proteins
Part: 2
Dr. Ifat Ara Begum
Associate Professor
Department of Biochemistry
Dhaka Medical College, Dhaka
8/17/2021 1
Dr Ifat, dept of Biochemistry, DMC
Learning Objectives
 Classification of proteins
 Sources of proteins
 Properties of proteins: Isoelectric pH
 Different structures of proteins
 Denaturation of proteins
 Functions of proteins
8/17/2021 2
Dr Ifat, dept of Biochemistry, DMC
8/17/2021 3
Dr Ifat, dept of Biochemistry, DMC
Types Function Example Types Function Example
i)
Structural
Protein
Support
framework
of cell
Collagen, Elastin,
etc
v) Gene
regulatory
Protein
Regulate
genetic
functions
Histone,
Protamine
ii)
Catalytic
Protein
Catalysis Enzymes vi) Protective
Protein
Prevent
infection
Immunoglobulin
iii)
Transport
Protein
Transport of
substances
Albumin,
Transferrin
vii) Receptor
Protein
Receptor
function
LDL receptor
iv)
Hormonal
Protein
Regulation of
functions
Insulin, Glucagon viii)
Contractile
Protein
Muscle
contraction
Actin, Myosin
A) Functional Classification of Proteins
8/17/2021 4
Dr Ifat, dept of Biochemistry, DMC
Points i) Simple protein ii) Conjugated protein iii) Derived protein
Composition Composed of amino acid
residues without any non
protein substances
Composed of protein along
with non protein prosthetic
substances
Denatured / degraded
products of simple
protein & conjugated
protein
On
hydrolysis
They produce only amino acids They produce amino acid
plus other non amino acid
substances
-
Types 2 types: Fibrous protein &
Globular protein
- -
Example Fibrous: Collagen, elastin,
keratin etc
Globular: Albumin, globulin etc
Nucleoprotein, lipoprotein
etc
Proteose, peptone, PP,
peptides
B) Classification of proteins based on their size, shape & solubility
8/17/2021 5
Dr Ifat, dept of Biochemistry, DMC
Points Fibrous protein Globular protein
Synonym Scleroprotein Spheroprotein
Shape Fibre like with high tensile strength Oval / spherical
MW High Relatively low
Origin Entirely animal origin -
Water solubility Insoluble Soluble
Digestibility Highly resistant to proteolytic enzymes Digestible by proteolytic enzymes
Site Tendons, ligaments, cartilage, hair, nail
etc
-
Example Collagen, elastin, keratin etc Albumin, globulin, histone,
protamine etc
8/17/2021 6
Dr Ifat, dept of Biochemistry, DMC
Conjugated protein Prosthetic / Non protein groups
Nucleoprotein Nucleic acid (DNA , RNA)
Lipoprotein Lipid
Glycoprotein Carbohydrate (oligosaccharide)
Hemoglobin, myoglobin,
peroxidase, catalase, cytochrome
Heme
Ferritin Iron
Ceruloplasmin Copper
Carbonic anhydrase Zinc
8/17/2021 7
Dr Ifat, dept of Biochemistry, DMC
Points i) Complete protein ii) Incomplete protein iii) Partially
incomplete protein
Composition Contains all essential
amino acids
Completely lack one or
more essential amino
acids
Partially lack one or
more essential amino
acids
Role on
growth
Promotes growth Can not promote growth -
Example Egg albumin, meat etc Gelatin (lacks Trp) Wheat protein
C) Nutritional classification of proteins
8/17/2021 8
Dr Ifat, dept of Biochemistry, DMC
8/17/2021 9
Dr Ifat, dept of Biochemistry, DMC
8/17/2021 10
Dr Ifat, dept of Biochemistry, DMC
8/17/2021 11
Dr Ifat, dept of Biochemistry, DMC
Physical Properties
 Macromolecule
 Shape: variable
 MW: Variable
 Shows differential solubility but
mostly water insoluble
 Forms colloidal solution with water
which is optically active
Chemical Properties
 Amphoteric / Ampholyte in nature
 Acts as buffer
 Heat labile (Denatured / coagulated by
heat)
 Expresses charge on the surface
 Have a definite iso-electric pH
 Gives colour reaction with
 ninhydrin reagent
 biuret reagent
8/17/2021 12
Dr Ifat, Dept of Biochemistry, DMC
8/17/2021 13
Dr Ifat, dept of Biochemistry, DMC
Proteins exist as Zwitter ion / Dipolar form at isoelectric pH
Isoelectric point (pI)/ Isoelectric pH:
It is the pH of an aqueous solution of an amino acid (or protein) at which the
molecules on average have no net charge.
8/17/2021 14
Dr Ifat, dept of Biochemistry, DMC
 Usually described at 4 levels
of organization
 Any alteration in the
structure or sequencing, will
change the properties and
functions of the protein
8/17/2021 15
Dr Ifat, dept of Biochemistry, DMC
8/17/2021 16
Dr Ifat, dept of Biochemistry, DMC
 Exact linear sequence of amino acids in a protein held together by peptide bonds
 Each Amino acid in a polypeptide chain is termed as amino acid residue
 N-terminal end / Amino end: The free NH2 group of one terminal amino acid,
traditionally assumed to be on left hand side of a PP chain
 C-terminal end / Carboxyl end: The free COOH group of another terminal amino acid,
traditionally assumed to be on right hand side of a PP chain
 Sequence of amino acids is written from N-terminus to the C-terminus
8/17/2021 17
Dr Ifat, dept of Biochemistry, DMC
A) Primary Structure
 Primary structure of a protein is
determined genetically and this
in turn determines the secondary,
tertiary & quaternary structure
of that protein
 Any change in the sequence of
amino acids in a peptide / PP
chain is abnormal & may affect
the properties and functions of
the protein
8/17/2021 18
Dr Ifat, dept of Biochemistry, DMC
Why called Amino acid residue ?
Because, amino acids in the peptide / polypeptide chains have already lost
the atoms of water during formation of peptide bonds among them
8/17/2021 19
Dr Ifat, dept of Biochemistry, DMC
8/17/2021 20
Dr Ifat, dept of Biochemistry, DMC
Helical Structure:
It is produced like a
spiral staircase
around the central
axis.
Pleated sheet :
It is formed by
hydrogen bond
between 2 extended
polypeptide chains
B) Secondary Structure:Formed by periodic folding, twisting or coiling of its
primary structure
8/17/2021 21
Dr Ifat, dept of Biochemistry, DMC
8/17/2021 22
Dr Ifat, dept of Biochemistry, DMC
D) Quaternary Structure
C) Tertiary Structure
Points A) Primary
structure
B) Secondary
structure
C) Tertiary
structure
D) Quaternary
structure
What is it? Exact linear
sequence of amino
acids in a protein
held together by
peptide bonds
The Helical or
pleated sheet
like protein
The three dimensional
globular form of protein
A multi chain oligomeric
protein
How
formed?
By joining a
number of amino
acids whose
sequence is
determined
genetically
By periodic
folding, twisting
or coiling of its
primary
structure
By further folding &
twisting of a secondary
structure of protein
about itself keeping the
hydrophobic side chains
buried interiorly &
hydrophilic groups
exposed outside
By joining of 2 or more
polypeptide chains (same /
different type) at a definite
spatial relationship.
(Individual PP chain is
called monomer/ subunit)
8/17/2021 23
Dr Ifat, dept of Biochemistry, DMC
Points A) Primary
structure
B) Secondary
structure
C) Tertiary
structure
D) Quaternary
structure
Any
specialty?
It determines the
secondary,
tertiary &
quaternary
structure of a
specific protein
2 types of conformation:
i) Helical form
ii) Pleated sheet form
It is the overall shape
of a single protein
unit.
The protein is
functionally active at
this level
Collection of single
protein units at tertiary
level.
Specific
Bond (S)
- Peptide bond
(Mainly)
- Di sulfide bond
- Peptide bond
- Di sulfide bond
- Hydrogen bond
- Peptide bond
- Di sulfide bond
- Hydrogen bond
- Ionic bond
- Hydrophobic bonds
- Van der walls force
Same as tertiary
structure :
- Peptide bond
- Di sulfide bond
- Hydrogen bond
- Ionic bond
- Hydrophobic bonds
- Van der walls force
8/17/2021 24
Dr Ifat, dept of Biochemistry, DMC
Points Primary
structure
Secondary
structure
Tertiary
structure
Quaternary
structure
Example Insulin Fibrous protein
(collagen, elastin,
keratin)
Albumin, globulin,
antibody etc.
Hb, Insulin, CPK,
LDH etc
8/17/2021 25
Dr Ifat, dept of Biochemistry, DMC
8/17/2021 26
Dr Ifat, dept of Biochemistry, DMC
Disulfide bond:
(–S–S–) formed by the coupling of two thiol (–SH) groups.
Cysteine has thiol group in its side chain.
8/17/2021 Dr Ifat, dept of Biochemistry, DMC 27
8/17/2021 Dr Ifat, dept of Biochemistry, DMC 28
 It is the process of disruption &
possible destruction of of protein’s
secondary, tertiary & quaternary
structures while preserving the
primary structure.
 It is not accompanied by hydrolysis
of peptide bond.
 No intra molecular change (no
change in MW)
 Change occurs in properties of
proteins
8/17/2021 29
Dr Ifat, dept of Biochemistry, DMC
Denaturation
Usually Irreversible
(e.g. Boiled egg, cooked
meat / fish etc )
Reversible
(Under ideal condition.
e.g. Ribonuclease at high urea
conc. )
8/17/2021 30
Dr Ifat, dept of Biochemistry, DMC
Denaturing agents:
 Physical agent: Extremes of temperature,
ultra sound, UV radiation etc
 Chemical agents: Extreme pH, strong acid /
alkali, detergent, heavy metals etc
8/17/2021 31
Dr Ifat, dept of Biochemistry, DMC
Changes in protein following denaturation
 Physical change:
 Increased viscosity
Decreased diffusibility
 Chemical change:
 Increased chance of precipitation
 Decreased solubility
 Biological change :
 Loss of function
Increased digestibility by proteolytic enzymes
8/17/2021 32
Dr Ifat, dept of Biochemistry, DMC
8/17/2021 33
Dr Ifat, dept of Biochemistry, DMC
 Source of energy
 Formation of cytoskeleton
(Flexible structural
framework for cells / tissues)
 Provides :
 Mechanical support: By structural protein
like collagen, elastin
 Defense against infection: By antibody like
immunoglobulin
 Helps in:
 Muscle contraction : By
contractile protein like actin,
myosin
 Coagulation : By clotting factors
8/17/2021 34
Dr Ifat, Dept of Biochemistry, DMC
 Acts as:
 Vehicle for transport of diff molecules
like hormones, drugs, vitamins etc
 Buffer
 Promotes:
 Catalytic function by enzymes
 Hormonal functions by hormones
 Plasma proteins maintain COP of
plasma to maintain blood volume
8/17/2021 35
Dr Ifat, Dept of Biochemistry, DMC
 Storage, expression & transmission of genetic information by
nucleoprotein
8/17/2021 36
Dr Ifat, Dept of Biochemistry, DMC

More Related Content

What's hot

chemistry of protein.ppt
chemistry of protein.pptchemistry of protein.ppt
chemistry of protein.ppt
NiranjanShakya1
 
Amino Acids.pptx
Amino Acids.pptxAmino Acids.pptx
Amino Acids.pptx
Kayeen Vadakkan
 
The proteins metabolism
The proteins metabolismThe proteins metabolism
The proteins metabolism
Dr Hakim Mehenni
 
Biochemistry ii protein (metabolism of amino acids) (new edition)
Biochemistry ii protein (metabolism of amino acids) (new edition)Biochemistry ii protein (metabolism of amino acids) (new edition)
Biochemistry ii protein (metabolism of amino acids) (new edition)
abdulhussien aljebory
 
Inborn Errors of Aminoacid Metabolism
Inborn Errors of Aminoacid MetabolismInborn Errors of Aminoacid Metabolism
Inborn Errors of Aminoacid Metabolism
All India Institute of Medical Sciences, Mangalagiri
 
Pyruvate Dehydrogenase and Tricarboxylic Acid Cycle - PDH and TCA
Pyruvate Dehydrogenase and Tricarboxylic Acid Cycle - PDH and TCAPyruvate Dehydrogenase and Tricarboxylic Acid Cycle - PDH and TCA
Pyruvate Dehydrogenase and Tricarboxylic Acid Cycle - PDH and TCA
Chetan Ganteppanavar
 
Ketone body metabolism
Ketone body metabolismKetone body metabolism
Protein metabolism
Protein metabolismProtein metabolism
Protein metabolism
Jaleelkabdul Jaleel
 
Metabolism- Biochemistry
Metabolism- BiochemistryMetabolism- Biochemistry
Metabolism- Biochemistry
Burhan Umer
 
Structure Of Protein
Structure Of ProteinStructure Of Protein
Structure Of Protein
AMIR HASSAN
 
Introduction to biochemistry
Introduction to biochemistryIntroduction to biochemistry
Introduction to biochemistry
Taw Alzu
 
Amino acid
Amino acid Amino acid
Amino acid
sridarshini chandra
 
VITAMINS
VITAMINSVITAMINS
VITAMINS
DrRakeshKGupta
 
Classification of Amino Acids by farhan ali
Classification of Amino Acids by farhan aliClassification of Amino Acids by farhan ali
Classification of Amino Acids by farhan ali
Farhan Ali
 
Isoenzymes
IsoenzymesIsoenzymes
Isoenzymes
Gokul Sampath
 
Vitamins
VitaminsVitamins
Vitamins
Neha Gupta
 
8. Factors affecting microbial growth
8. Factors affecting microbial growth8. Factors affecting microbial growth
8. Factors affecting microbial growth
VISHAKHABORKAR3
 
Vitamins Vitamins
Vitamins VitaminsVitamins Vitamins
Vitamins Vitamins
ROMAN BAJRANG
 
Classification and nomenclature of enzymes
Classification and nomenclature of enzymesClassification and nomenclature of enzymes
Classification and nomenclature of enzymes
HARINATHA REDDY ASWARTHA
 
Enzymes (General Introduction & Action Mechanism)
Enzymes (General Introduction & Action Mechanism) Enzymes (General Introduction & Action Mechanism)
Enzymes (General Introduction & Action Mechanism)
Dr. Mohammedazim Bagban
 

What's hot (20)

chemistry of protein.ppt
chemistry of protein.pptchemistry of protein.ppt
chemistry of protein.ppt
 
Amino Acids.pptx
Amino Acids.pptxAmino Acids.pptx
Amino Acids.pptx
 
The proteins metabolism
The proteins metabolismThe proteins metabolism
The proteins metabolism
 
Biochemistry ii protein (metabolism of amino acids) (new edition)
Biochemistry ii protein (metabolism of amino acids) (new edition)Biochemistry ii protein (metabolism of amino acids) (new edition)
Biochemistry ii protein (metabolism of amino acids) (new edition)
 
Inborn Errors of Aminoacid Metabolism
Inborn Errors of Aminoacid MetabolismInborn Errors of Aminoacid Metabolism
Inborn Errors of Aminoacid Metabolism
 
Pyruvate Dehydrogenase and Tricarboxylic Acid Cycle - PDH and TCA
Pyruvate Dehydrogenase and Tricarboxylic Acid Cycle - PDH and TCAPyruvate Dehydrogenase and Tricarboxylic Acid Cycle - PDH and TCA
Pyruvate Dehydrogenase and Tricarboxylic Acid Cycle - PDH and TCA
 
Ketone body metabolism
Ketone body metabolismKetone body metabolism
Ketone body metabolism
 
Protein metabolism
Protein metabolismProtein metabolism
Protein metabolism
 
Metabolism- Biochemistry
Metabolism- BiochemistryMetabolism- Biochemistry
Metabolism- Biochemistry
 
Structure Of Protein
Structure Of ProteinStructure Of Protein
Structure Of Protein
 
Introduction to biochemistry
Introduction to biochemistryIntroduction to biochemistry
Introduction to biochemistry
 
Amino acid
Amino acid Amino acid
Amino acid
 
VITAMINS
VITAMINSVITAMINS
VITAMINS
 
Classification of Amino Acids by farhan ali
Classification of Amino Acids by farhan aliClassification of Amino Acids by farhan ali
Classification of Amino Acids by farhan ali
 
Isoenzymes
IsoenzymesIsoenzymes
Isoenzymes
 
Vitamins
VitaminsVitamins
Vitamins
 
8. Factors affecting microbial growth
8. Factors affecting microbial growth8. Factors affecting microbial growth
8. Factors affecting microbial growth
 
Vitamins Vitamins
Vitamins VitaminsVitamins Vitamins
Vitamins Vitamins
 
Classification and nomenclature of enzymes
Classification and nomenclature of enzymesClassification and nomenclature of enzymes
Classification and nomenclature of enzymes
 
Enzymes (General Introduction & Action Mechanism)
Enzymes (General Introduction & Action Mechanism) Enzymes (General Introduction & Action Mechanism)
Enzymes (General Introduction & Action Mechanism)
 

Similar to Chemistry of protein, part 2 (Aug'21)

50th MBBS, Chemistry of protein, Part 2.pptx
50th MBBS, Chemistry of protein, Part 2.pptx50th MBBS, Chemistry of protein, Part 2.pptx
50th MBBS, Chemistry of protein, Part 2.pptx
isratsadia
 
Protein and peptides drug delivery systems
Protein and peptides drug delivery systemsProtein and peptides drug delivery systems
Protein and peptides drug delivery systems
VINOTH R
 
Proteins folding and denaturation
Proteins folding and denaturation Proteins folding and denaturation
Proteins folding and denaturation
Bahauddin zakariya university,Multan
 
Protein and peptide d d s
Protein and peptide d d sProtein and peptide d d s
Protein and peptide d d s
Malla Reddy College of Pharmacy
 
Physical aspects, biochemistry of protein & peptide
Physical aspects, biochemistry of protein & peptidePhysical aspects, biochemistry of protein & peptide
Physical aspects, biochemistry of protein & peptide
Shubham Talpe
 
Proteins and peptides dds
Proteins and peptides ddsProteins and peptides dds
Proteins and peptides dds
AshwiniBawankule
 
Protein bph
Protein bphProtein bph
Protein bph
RaNa MB
 
Lecture 1. Proteins.-1.doc
Lecture 1. Proteins.-1.docLecture 1. Proteins.-1.doc
Lecture 1. Proteins.-1.doc
MedicalStudent58
 
Practical consideration of protien and peptides
Practical consideration of protien and peptidesPractical consideration of protien and peptides
Practical consideration of protien and peptides
Suchandra03
 
Session no. 2.2. biological molecules proteins and enzymes
Session no. 2.2. biological molecules proteins and enzymesSession no. 2.2. biological molecules proteins and enzymes
Session no. 2.2. biological molecules proteins and enzymes
anonymous143
 
Protein.pdf
Protein.pdfProtein.pdf
Protein.pdf
JanuMethnodh
 
CELLULAR METABOLISM AND METABOLIC DISORDERS.pptx
CELLULAR METABOLISM AND METABOLIC DISORDERS.pptxCELLULAR METABOLISM AND METABOLIC DISORDERS.pptx
CELLULAR METABOLISM AND METABOLIC DISORDERS.pptx
MurtiKiya
 
Proteins.pptx
Proteins.pptxProteins.pptx
Proteins.pptx
Aditi Sharma
 
Barrier to protein & peptited delivery
Barrier to protein & peptited deliveryBarrier to protein & peptited delivery
Barrier to protein & peptited delivery
aishwaryaPatil86
 
Protein Denaturation & Protein Purification
Protein Denaturation & Protein PurificationProtein Denaturation & Protein Purification
Protein Denaturation & Protein Purification
Debashish24
 
1. intro,aa& prot
1. intro,aa& prot1. intro,aa& prot
1. intro,aa& prot
Lecturer at Wolkite University
 
PROTEIN AND PEPTIDE DELIVERY adiya 5.pdf
PROTEIN AND PEPTIDE DELIVERY adiya 5.pdfPROTEIN AND PEPTIDE DELIVERY adiya 5.pdf
PROTEIN AND PEPTIDE DELIVERY adiya 5.pdf
ADITYACHAUDHARY377908
 
IB Biology 2.4 & 7.3 Slides: Proteins
IB Biology 2.4 & 7.3 Slides: ProteinsIB Biology 2.4 & 7.3 Slides: Proteins
IB Biology 2.4 & 7.3 Slides: Proteins
Jacob Cedarbaum
 
Thermodynamic and biophysical characterization of cytochrome p450 bio i from ...
Thermodynamic and biophysical characterization of cytochrome p450 bio i from ...Thermodynamic and biophysical characterization of cytochrome p450 bio i from ...
Thermodynamic and biophysical characterization of cytochrome p450 bio i from ...
John Clarkson
 
report
reportreport

Similar to Chemistry of protein, part 2 (Aug'21) (20)

50th MBBS, Chemistry of protein, Part 2.pptx
50th MBBS, Chemistry of protein, Part 2.pptx50th MBBS, Chemistry of protein, Part 2.pptx
50th MBBS, Chemistry of protein, Part 2.pptx
 
Protein and peptides drug delivery systems
Protein and peptides drug delivery systemsProtein and peptides drug delivery systems
Protein and peptides drug delivery systems
 
Proteins folding and denaturation
Proteins folding and denaturation Proteins folding and denaturation
Proteins folding and denaturation
 
Protein and peptide d d s
Protein and peptide d d sProtein and peptide d d s
Protein and peptide d d s
 
Physical aspects, biochemistry of protein & peptide
Physical aspects, biochemistry of protein & peptidePhysical aspects, biochemistry of protein & peptide
Physical aspects, biochemistry of protein & peptide
 
Proteins and peptides dds
Proteins and peptides ddsProteins and peptides dds
Proteins and peptides dds
 
Protein bph
Protein bphProtein bph
Protein bph
 
Lecture 1. Proteins.-1.doc
Lecture 1. Proteins.-1.docLecture 1. Proteins.-1.doc
Lecture 1. Proteins.-1.doc
 
Practical consideration of protien and peptides
Practical consideration of protien and peptidesPractical consideration of protien and peptides
Practical consideration of protien and peptides
 
Session no. 2.2. biological molecules proteins and enzymes
Session no. 2.2. biological molecules proteins and enzymesSession no. 2.2. biological molecules proteins and enzymes
Session no. 2.2. biological molecules proteins and enzymes
 
Protein.pdf
Protein.pdfProtein.pdf
Protein.pdf
 
CELLULAR METABOLISM AND METABOLIC DISORDERS.pptx
CELLULAR METABOLISM AND METABOLIC DISORDERS.pptxCELLULAR METABOLISM AND METABOLIC DISORDERS.pptx
CELLULAR METABOLISM AND METABOLIC DISORDERS.pptx
 
Proteins.pptx
Proteins.pptxProteins.pptx
Proteins.pptx
 
Barrier to protein & peptited delivery
Barrier to protein & peptited deliveryBarrier to protein & peptited delivery
Barrier to protein & peptited delivery
 
Protein Denaturation & Protein Purification
Protein Denaturation & Protein PurificationProtein Denaturation & Protein Purification
Protein Denaturation & Protein Purification
 
1. intro,aa& prot
1. intro,aa& prot1. intro,aa& prot
1. intro,aa& prot
 
PROTEIN AND PEPTIDE DELIVERY adiya 5.pdf
PROTEIN AND PEPTIDE DELIVERY adiya 5.pdfPROTEIN AND PEPTIDE DELIVERY adiya 5.pdf
PROTEIN AND PEPTIDE DELIVERY adiya 5.pdf
 
IB Biology 2.4 & 7.3 Slides: Proteins
IB Biology 2.4 & 7.3 Slides: ProteinsIB Biology 2.4 & 7.3 Slides: Proteins
IB Biology 2.4 & 7.3 Slides: Proteins
 
Thermodynamic and biophysical characterization of cytochrome p450 bio i from ...
Thermodynamic and biophysical characterization of cytochrome p450 bio i from ...Thermodynamic and biophysical characterization of cytochrome p450 bio i from ...
Thermodynamic and biophysical characterization of cytochrome p450 bio i from ...
 
report
reportreport
report
 

More from enamifat

Thyroid Function test.pptx
Thyroid Function test.pptxThyroid Function test.pptx
Thyroid Function test.pptx
enamifat
 
Chemistry of protein, part 1 (Aug'21)
Chemistry of protein, part 1 (Aug'21)Chemistry of protein, part 1 (Aug'21)
Chemistry of protein, part 1 (Aug'21)
enamifat
 
Replication
ReplicationReplication
Replication
enamifat
 
Central Dogma, Gene, Genetic Code, Codon, Genome, Genotype, Phenotype , Trai...
Central Dogma, Gene,  Genetic Code, Codon, Genome, Genotype, Phenotype , Trai...Central Dogma, Gene,  Genetic Code, Codon, Genome, Genotype, Phenotype , Trai...
Central Dogma, Gene, Genetic Code, Codon, Genome, Genotype, Phenotype , Trai...
enamifat
 
Acid base balance (updated in 2020)
Acid base balance (updated in 2020)Acid base balance (updated in 2020)
Acid base balance (updated in 2020)
enamifat
 
Solution, crystalloids , colloids, isotope
Solution, crystalloids , colloids, isotope Solution, crystalloids , colloids, isotope
Solution, crystalloids , colloids, isotope
enamifat
 
Chemistry of lipid , september 2020
Chemistry of lipid , september 2020Chemistry of lipid , september 2020
Chemistry of lipid , september 2020
enamifat
 
Protein metabolism, july'20
Protein metabolism, july'20Protein metabolism, july'20
Protein metabolism, july'20
enamifat
 
Water soluble vitamins , june, 2020
Water soluble vitamins , june, 2020Water soluble vitamins , june, 2020
Water soluble vitamins , june, 2020
enamifat
 
Rna , ribosome and cell cycle, july 2020
Rna , ribosome and cell cycle, july 2020Rna , ribosome and cell cycle, july 2020
Rna , ribosome and cell cycle, july 2020
enamifat
 
Structure of dna, its organization & functions, july 2020
Structure of dna, its organization & functions, july 2020Structure of dna, its organization & functions, july 2020
Structure of dna, its organization & functions, july 2020
enamifat
 
Introduction to nucleic acid, chemistry of nucleotiides , july 2020
Introduction to nucleic acid, chemistry of nucleotiides , july 2020Introduction to nucleic acid, chemistry of nucleotiides , july 2020
Introduction to nucleic acid, chemistry of nucleotiides , july 2020
enamifat
 
Replication (reviewed, 2018)
Replication (reviewed, 2018)Replication (reviewed, 2018)
Replication (reviewed, 2018)
enamifat
 
Chemistry of enzyme
Chemistry of enzymeChemistry of enzyme
Chemistry of enzyme
enamifat
 
Chemistry of carbohydrates
Chemistry of carbohydratesChemistry of carbohydrates
Chemistry of carbohydrates
enamifat
 
Metabolism of protein
Metabolism of protein Metabolism of protein
Metabolism of protein
enamifat
 
Chemistry of protein
Chemistry of protein Chemistry of protein
Chemistry of protein
enamifat
 
Chemistry of digestion &; absorption
Chemistry of digestion &; absorption Chemistry of digestion &; absorption
Chemistry of digestion &; absorption
enamifat
 
Vitamins
Vitamins Vitamins
Vitamins
enamifat
 
Acid base balance, acid base disorder
Acid base balance, acid base disorderAcid base balance, acid base disorder
Acid base balance, acid base disorder
enamifat
 

More from enamifat (20)

Thyroid Function test.pptx
Thyroid Function test.pptxThyroid Function test.pptx
Thyroid Function test.pptx
 
Chemistry of protein, part 1 (Aug'21)
Chemistry of protein, part 1 (Aug'21)Chemistry of protein, part 1 (Aug'21)
Chemistry of protein, part 1 (Aug'21)
 
Replication
ReplicationReplication
Replication
 
Central Dogma, Gene, Genetic Code, Codon, Genome, Genotype, Phenotype , Trai...
Central Dogma, Gene,  Genetic Code, Codon, Genome, Genotype, Phenotype , Trai...Central Dogma, Gene,  Genetic Code, Codon, Genome, Genotype, Phenotype , Trai...
Central Dogma, Gene, Genetic Code, Codon, Genome, Genotype, Phenotype , Trai...
 
Acid base balance (updated in 2020)
Acid base balance (updated in 2020)Acid base balance (updated in 2020)
Acid base balance (updated in 2020)
 
Solution, crystalloids , colloids, isotope
Solution, crystalloids , colloids, isotope Solution, crystalloids , colloids, isotope
Solution, crystalloids , colloids, isotope
 
Chemistry of lipid , september 2020
Chemistry of lipid , september 2020Chemistry of lipid , september 2020
Chemistry of lipid , september 2020
 
Protein metabolism, july'20
Protein metabolism, july'20Protein metabolism, july'20
Protein metabolism, july'20
 
Water soluble vitamins , june, 2020
Water soluble vitamins , june, 2020Water soluble vitamins , june, 2020
Water soluble vitamins , june, 2020
 
Rna , ribosome and cell cycle, july 2020
Rna , ribosome and cell cycle, july 2020Rna , ribosome and cell cycle, july 2020
Rna , ribosome and cell cycle, july 2020
 
Structure of dna, its organization & functions, july 2020
Structure of dna, its organization & functions, july 2020Structure of dna, its organization & functions, july 2020
Structure of dna, its organization & functions, july 2020
 
Introduction to nucleic acid, chemistry of nucleotiides , july 2020
Introduction to nucleic acid, chemistry of nucleotiides , july 2020Introduction to nucleic acid, chemistry of nucleotiides , july 2020
Introduction to nucleic acid, chemistry of nucleotiides , july 2020
 
Replication (reviewed, 2018)
Replication (reviewed, 2018)Replication (reviewed, 2018)
Replication (reviewed, 2018)
 
Chemistry of enzyme
Chemistry of enzymeChemistry of enzyme
Chemistry of enzyme
 
Chemistry of carbohydrates
Chemistry of carbohydratesChemistry of carbohydrates
Chemistry of carbohydrates
 
Metabolism of protein
Metabolism of protein Metabolism of protein
Metabolism of protein
 
Chemistry of protein
Chemistry of protein Chemistry of protein
Chemistry of protein
 
Chemistry of digestion &; absorption
Chemistry of digestion &; absorption Chemistry of digestion &; absorption
Chemistry of digestion &; absorption
 
Vitamins
Vitamins Vitamins
Vitamins
 
Acid base balance, acid base disorder
Acid base balance, acid base disorderAcid base balance, acid base disorder
Acid base balance, acid base disorder
 

Recently uploaded

Top 10 Best Ayurvedic Kidney Stone Syrups in India
Top 10 Best Ayurvedic Kidney Stone Syrups in IndiaTop 10 Best Ayurvedic Kidney Stone Syrups in India
Top 10 Best Ayurvedic Kidney Stone Syrups in India
Swastik Ayurveda
 
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotes
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotesPromoting Wellbeing - Applied Social Psychology - Psychology SuperNotes
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotes
PsychoTech Services
 
Netter's Atlas of Human Anatomy 7.ed.pdf
Netter's Atlas of Human Anatomy 7.ed.pdfNetter's Atlas of Human Anatomy 7.ed.pdf
Netter's Atlas of Human Anatomy 7.ed.pdf
BrissaOrtiz3
 
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdfCHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
rishi2789
 
Journal Article Review on Rasamanikya
Journal Article Review on RasamanikyaJournal Article Review on Rasamanikya
Journal Article Review on Rasamanikya
Dr. Jyothirmai Paindla
 
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
Donc Test
 
Light House Retreats: Plant Medicine Retreat Europe
Light House Retreats: Plant Medicine Retreat EuropeLight House Retreats: Plant Medicine Retreat Europe
Light House Retreats: Plant Medicine Retreat Europe
Lighthouse Retreat
 
The Best Ayurvedic Antacid Tablets in India
The Best Ayurvedic Antacid Tablets in IndiaThe Best Ayurvedic Antacid Tablets in India
The Best Ayurvedic Antacid Tablets in India
Swastik Ayurveda
 
The Electrocardiogram - Physiologic Principles
The Electrocardiogram - Physiologic PrinciplesThe Electrocardiogram - Physiologic Principles
The Electrocardiogram - Physiologic Principles
MedicoseAcademics
 
Tests for analysis of different pharmaceutical.pptx
Tests for analysis of different pharmaceutical.pptxTests for analysis of different pharmaceutical.pptx
Tests for analysis of different pharmaceutical.pptx
taiba qazi
 
NVBDCP.pptx Nation vector borne disease control program
NVBDCP.pptx Nation vector borne disease control programNVBDCP.pptx Nation vector borne disease control program
NVBDCP.pptx Nation vector borne disease control program
Sapna Thakur
 
Cardiac Assessment for B.sc Nursing Student.pdf
Cardiac Assessment for B.sc Nursing Student.pdfCardiac Assessment for B.sc Nursing Student.pdf
Cardiac Assessment for B.sc Nursing Student.pdf
shivalingatalekar1
 
Does Over-Masturbation Contribute to Chronic Prostatitis.pptx
Does Over-Masturbation Contribute to Chronic Prostatitis.pptxDoes Over-Masturbation Contribute to Chronic Prostatitis.pptx
Does Over-Masturbation Contribute to Chronic Prostatitis.pptx
walterHu5
 
Chapter 11 Nutrition and Chronic Diseases.pptx
Chapter 11 Nutrition and Chronic Diseases.pptxChapter 11 Nutrition and Chronic Diseases.pptx
Chapter 11 Nutrition and Chronic Diseases.pptx
Earlene McNair
 
Hemodialysis: Chapter 4, Dialysate Circuit - Dr.Gawad
Hemodialysis: Chapter 4, Dialysate Circuit - Dr.GawadHemodialysis: Chapter 4, Dialysate Circuit - Dr.Gawad
Hemodialysis: Chapter 4, Dialysate Circuit - Dr.Gawad
NephroTube - Dr.Gawad
 
Dehradun #ℂall #gIRLS Oyo Hotel 8107221448 #ℂall #gIRL in Dehradun
Dehradun #ℂall #gIRLS Oyo Hotel 8107221448 #ℂall #gIRL in DehradunDehradun #ℂall #gIRLS Oyo Hotel 8107221448 #ℂall #gIRL in Dehradun
Dehradun #ℂall #gIRLS Oyo Hotel 8107221448 #ℂall #gIRL in Dehradun
chandankumarsmartiso
 
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
Holistified Wellness
 
Phone Us ❤8107221448❤ #ℂall #gIRLS In Dehradun By Dehradun @ℂall @Girls Hotel...
Phone Us ❤8107221448❤ #ℂall #gIRLS In Dehradun By Dehradun @ℂall @Girls Hotel...Phone Us ❤8107221448❤ #ℂall #gIRLS In Dehradun By Dehradun @ℂall @Girls Hotel...
Phone Us ❤8107221448❤ #ℂall #gIRLS In Dehradun By Dehradun @ℂall @Girls Hotel...
chandankumarsmartiso
 
#cALL# #gIRLS# In Dehradun ꧁❤8107221448❤꧂#cALL# #gIRLS# Service In Dehradun W...
#cALL# #gIRLS# In Dehradun ꧁❤8107221448❤꧂#cALL# #gIRLS# Service In Dehradun W...#cALL# #gIRLS# In Dehradun ꧁❤8107221448❤꧂#cALL# #gIRLS# Service In Dehradun W...
#cALL# #gIRLS# In Dehradun ꧁❤8107221448❤꧂#cALL# #gIRLS# Service In Dehradun W...
chandankumarsmartiso
 
Vestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptx
Vestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptxVestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptx
Vestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptx
Dr. Rabia Inam Gandapore
 

Recently uploaded (20)

Top 10 Best Ayurvedic Kidney Stone Syrups in India
Top 10 Best Ayurvedic Kidney Stone Syrups in IndiaTop 10 Best Ayurvedic Kidney Stone Syrups in India
Top 10 Best Ayurvedic Kidney Stone Syrups in India
 
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotes
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotesPromoting Wellbeing - Applied Social Psychology - Psychology SuperNotes
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotes
 
Netter's Atlas of Human Anatomy 7.ed.pdf
Netter's Atlas of Human Anatomy 7.ed.pdfNetter's Atlas of Human Anatomy 7.ed.pdf
Netter's Atlas of Human Anatomy 7.ed.pdf
 
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdfCHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
 
Journal Article Review on Rasamanikya
Journal Article Review on RasamanikyaJournal Article Review on Rasamanikya
Journal Article Review on Rasamanikya
 
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
 
Light House Retreats: Plant Medicine Retreat Europe
Light House Retreats: Plant Medicine Retreat EuropeLight House Retreats: Plant Medicine Retreat Europe
Light House Retreats: Plant Medicine Retreat Europe
 
The Best Ayurvedic Antacid Tablets in India
The Best Ayurvedic Antacid Tablets in IndiaThe Best Ayurvedic Antacid Tablets in India
The Best Ayurvedic Antacid Tablets in India
 
The Electrocardiogram - Physiologic Principles
The Electrocardiogram - Physiologic PrinciplesThe Electrocardiogram - Physiologic Principles
The Electrocardiogram - Physiologic Principles
 
Tests for analysis of different pharmaceutical.pptx
Tests for analysis of different pharmaceutical.pptxTests for analysis of different pharmaceutical.pptx
Tests for analysis of different pharmaceutical.pptx
 
NVBDCP.pptx Nation vector borne disease control program
NVBDCP.pptx Nation vector borne disease control programNVBDCP.pptx Nation vector borne disease control program
NVBDCP.pptx Nation vector borne disease control program
 
Cardiac Assessment for B.sc Nursing Student.pdf
Cardiac Assessment for B.sc Nursing Student.pdfCardiac Assessment for B.sc Nursing Student.pdf
Cardiac Assessment for B.sc Nursing Student.pdf
 
Does Over-Masturbation Contribute to Chronic Prostatitis.pptx
Does Over-Masturbation Contribute to Chronic Prostatitis.pptxDoes Over-Masturbation Contribute to Chronic Prostatitis.pptx
Does Over-Masturbation Contribute to Chronic Prostatitis.pptx
 
Chapter 11 Nutrition and Chronic Diseases.pptx
Chapter 11 Nutrition and Chronic Diseases.pptxChapter 11 Nutrition and Chronic Diseases.pptx
Chapter 11 Nutrition and Chronic Diseases.pptx
 
Hemodialysis: Chapter 4, Dialysate Circuit - Dr.Gawad
Hemodialysis: Chapter 4, Dialysate Circuit - Dr.GawadHemodialysis: Chapter 4, Dialysate Circuit - Dr.Gawad
Hemodialysis: Chapter 4, Dialysate Circuit - Dr.Gawad
 
Dehradun #ℂall #gIRLS Oyo Hotel 8107221448 #ℂall #gIRL in Dehradun
Dehradun #ℂall #gIRLS Oyo Hotel 8107221448 #ℂall #gIRL in DehradunDehradun #ℂall #gIRLS Oyo Hotel 8107221448 #ℂall #gIRL in Dehradun
Dehradun #ℂall #gIRLS Oyo Hotel 8107221448 #ℂall #gIRL in Dehradun
 
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
 
Phone Us ❤8107221448❤ #ℂall #gIRLS In Dehradun By Dehradun @ℂall @Girls Hotel...
Phone Us ❤8107221448❤ #ℂall #gIRLS In Dehradun By Dehradun @ℂall @Girls Hotel...Phone Us ❤8107221448❤ #ℂall #gIRLS In Dehradun By Dehradun @ℂall @Girls Hotel...
Phone Us ❤8107221448❤ #ℂall #gIRLS In Dehradun By Dehradun @ℂall @Girls Hotel...
 
#cALL# #gIRLS# In Dehradun ꧁❤8107221448❤꧂#cALL# #gIRLS# Service In Dehradun W...
#cALL# #gIRLS# In Dehradun ꧁❤8107221448❤꧂#cALL# #gIRLS# Service In Dehradun W...#cALL# #gIRLS# In Dehradun ꧁❤8107221448❤꧂#cALL# #gIRLS# Service In Dehradun W...
#cALL# #gIRLS# In Dehradun ꧁❤8107221448❤꧂#cALL# #gIRLS# Service In Dehradun W...
 
Vestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptx
Vestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptxVestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptx
Vestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptx
 

Chemistry of protein, part 2 (Aug'21)

  • 1. Amino Acids and Proteins Part: 2 Dr. Ifat Ara Begum Associate Professor Department of Biochemistry Dhaka Medical College, Dhaka 8/17/2021 1 Dr Ifat, dept of Biochemistry, DMC
  • 2. Learning Objectives  Classification of proteins  Sources of proteins  Properties of proteins: Isoelectric pH  Different structures of proteins  Denaturation of proteins  Functions of proteins 8/17/2021 2 Dr Ifat, dept of Biochemistry, DMC
  • 3. 8/17/2021 3 Dr Ifat, dept of Biochemistry, DMC
  • 4. Types Function Example Types Function Example i) Structural Protein Support framework of cell Collagen, Elastin, etc v) Gene regulatory Protein Regulate genetic functions Histone, Protamine ii) Catalytic Protein Catalysis Enzymes vi) Protective Protein Prevent infection Immunoglobulin iii) Transport Protein Transport of substances Albumin, Transferrin vii) Receptor Protein Receptor function LDL receptor iv) Hormonal Protein Regulation of functions Insulin, Glucagon viii) Contractile Protein Muscle contraction Actin, Myosin A) Functional Classification of Proteins 8/17/2021 4 Dr Ifat, dept of Biochemistry, DMC
  • 5. Points i) Simple protein ii) Conjugated protein iii) Derived protein Composition Composed of amino acid residues without any non protein substances Composed of protein along with non protein prosthetic substances Denatured / degraded products of simple protein & conjugated protein On hydrolysis They produce only amino acids They produce amino acid plus other non amino acid substances - Types 2 types: Fibrous protein & Globular protein - - Example Fibrous: Collagen, elastin, keratin etc Globular: Albumin, globulin etc Nucleoprotein, lipoprotein etc Proteose, peptone, PP, peptides B) Classification of proteins based on their size, shape & solubility 8/17/2021 5 Dr Ifat, dept of Biochemistry, DMC
  • 6. Points Fibrous protein Globular protein Synonym Scleroprotein Spheroprotein Shape Fibre like with high tensile strength Oval / spherical MW High Relatively low Origin Entirely animal origin - Water solubility Insoluble Soluble Digestibility Highly resistant to proteolytic enzymes Digestible by proteolytic enzymes Site Tendons, ligaments, cartilage, hair, nail etc - Example Collagen, elastin, keratin etc Albumin, globulin, histone, protamine etc 8/17/2021 6 Dr Ifat, dept of Biochemistry, DMC
  • 7. Conjugated protein Prosthetic / Non protein groups Nucleoprotein Nucleic acid (DNA , RNA) Lipoprotein Lipid Glycoprotein Carbohydrate (oligosaccharide) Hemoglobin, myoglobin, peroxidase, catalase, cytochrome Heme Ferritin Iron Ceruloplasmin Copper Carbonic anhydrase Zinc 8/17/2021 7 Dr Ifat, dept of Biochemistry, DMC
  • 8. Points i) Complete protein ii) Incomplete protein iii) Partially incomplete protein Composition Contains all essential amino acids Completely lack one or more essential amino acids Partially lack one or more essential amino acids Role on growth Promotes growth Can not promote growth - Example Egg albumin, meat etc Gelatin (lacks Trp) Wheat protein C) Nutritional classification of proteins 8/17/2021 8 Dr Ifat, dept of Biochemistry, DMC
  • 9. 8/17/2021 9 Dr Ifat, dept of Biochemistry, DMC
  • 10. 8/17/2021 10 Dr Ifat, dept of Biochemistry, DMC
  • 11. 8/17/2021 11 Dr Ifat, dept of Biochemistry, DMC
  • 12. Physical Properties  Macromolecule  Shape: variable  MW: Variable  Shows differential solubility but mostly water insoluble  Forms colloidal solution with water which is optically active Chemical Properties  Amphoteric / Ampholyte in nature  Acts as buffer  Heat labile (Denatured / coagulated by heat)  Expresses charge on the surface  Have a definite iso-electric pH  Gives colour reaction with  ninhydrin reagent  biuret reagent 8/17/2021 12 Dr Ifat, Dept of Biochemistry, DMC
  • 13. 8/17/2021 13 Dr Ifat, dept of Biochemistry, DMC Proteins exist as Zwitter ion / Dipolar form at isoelectric pH Isoelectric point (pI)/ Isoelectric pH: It is the pH of an aqueous solution of an amino acid (or protein) at which the molecules on average have no net charge.
  • 14. 8/17/2021 14 Dr Ifat, dept of Biochemistry, DMC
  • 15.  Usually described at 4 levels of organization  Any alteration in the structure or sequencing, will change the properties and functions of the protein 8/17/2021 15 Dr Ifat, dept of Biochemistry, DMC
  • 16. 8/17/2021 16 Dr Ifat, dept of Biochemistry, DMC
  • 17.  Exact linear sequence of amino acids in a protein held together by peptide bonds  Each Amino acid in a polypeptide chain is termed as amino acid residue  N-terminal end / Amino end: The free NH2 group of one terminal amino acid, traditionally assumed to be on left hand side of a PP chain  C-terminal end / Carboxyl end: The free COOH group of another terminal amino acid, traditionally assumed to be on right hand side of a PP chain  Sequence of amino acids is written from N-terminus to the C-terminus 8/17/2021 17 Dr Ifat, dept of Biochemistry, DMC A) Primary Structure
  • 18.  Primary structure of a protein is determined genetically and this in turn determines the secondary, tertiary & quaternary structure of that protein  Any change in the sequence of amino acids in a peptide / PP chain is abnormal & may affect the properties and functions of the protein 8/17/2021 18 Dr Ifat, dept of Biochemistry, DMC
  • 19. Why called Amino acid residue ? Because, amino acids in the peptide / polypeptide chains have already lost the atoms of water during formation of peptide bonds among them 8/17/2021 19 Dr Ifat, dept of Biochemistry, DMC
  • 20. 8/17/2021 20 Dr Ifat, dept of Biochemistry, DMC Helical Structure: It is produced like a spiral staircase around the central axis. Pleated sheet : It is formed by hydrogen bond between 2 extended polypeptide chains B) Secondary Structure:Formed by periodic folding, twisting or coiling of its primary structure
  • 21. 8/17/2021 21 Dr Ifat, dept of Biochemistry, DMC
  • 22. 8/17/2021 22 Dr Ifat, dept of Biochemistry, DMC D) Quaternary Structure C) Tertiary Structure
  • 23. Points A) Primary structure B) Secondary structure C) Tertiary structure D) Quaternary structure What is it? Exact linear sequence of amino acids in a protein held together by peptide bonds The Helical or pleated sheet like protein The three dimensional globular form of protein A multi chain oligomeric protein How formed? By joining a number of amino acids whose sequence is determined genetically By periodic folding, twisting or coiling of its primary structure By further folding & twisting of a secondary structure of protein about itself keeping the hydrophobic side chains buried interiorly & hydrophilic groups exposed outside By joining of 2 or more polypeptide chains (same / different type) at a definite spatial relationship. (Individual PP chain is called monomer/ subunit) 8/17/2021 23 Dr Ifat, dept of Biochemistry, DMC
  • 24. Points A) Primary structure B) Secondary structure C) Tertiary structure D) Quaternary structure Any specialty? It determines the secondary, tertiary & quaternary structure of a specific protein 2 types of conformation: i) Helical form ii) Pleated sheet form It is the overall shape of a single protein unit. The protein is functionally active at this level Collection of single protein units at tertiary level. Specific Bond (S) - Peptide bond (Mainly) - Di sulfide bond - Peptide bond - Di sulfide bond - Hydrogen bond - Peptide bond - Di sulfide bond - Hydrogen bond - Ionic bond - Hydrophobic bonds - Van der walls force Same as tertiary structure : - Peptide bond - Di sulfide bond - Hydrogen bond - Ionic bond - Hydrophobic bonds - Van der walls force 8/17/2021 24 Dr Ifat, dept of Biochemistry, DMC
  • 25. Points Primary structure Secondary structure Tertiary structure Quaternary structure Example Insulin Fibrous protein (collagen, elastin, keratin) Albumin, globulin, antibody etc. Hb, Insulin, CPK, LDH etc 8/17/2021 25 Dr Ifat, dept of Biochemistry, DMC
  • 26. 8/17/2021 26 Dr Ifat, dept of Biochemistry, DMC Disulfide bond: (–S–S–) formed by the coupling of two thiol (–SH) groups. Cysteine has thiol group in its side chain.
  • 27. 8/17/2021 Dr Ifat, dept of Biochemistry, DMC 27
  • 28. 8/17/2021 Dr Ifat, dept of Biochemistry, DMC 28
  • 29.  It is the process of disruption & possible destruction of of protein’s secondary, tertiary & quaternary structures while preserving the primary structure.  It is not accompanied by hydrolysis of peptide bond.  No intra molecular change (no change in MW)  Change occurs in properties of proteins 8/17/2021 29 Dr Ifat, dept of Biochemistry, DMC
  • 30. Denaturation Usually Irreversible (e.g. Boiled egg, cooked meat / fish etc ) Reversible (Under ideal condition. e.g. Ribonuclease at high urea conc. ) 8/17/2021 30 Dr Ifat, dept of Biochemistry, DMC
  • 31. Denaturing agents:  Physical agent: Extremes of temperature, ultra sound, UV radiation etc  Chemical agents: Extreme pH, strong acid / alkali, detergent, heavy metals etc 8/17/2021 31 Dr Ifat, dept of Biochemistry, DMC
  • 32. Changes in protein following denaturation  Physical change:  Increased viscosity Decreased diffusibility  Chemical change:  Increased chance of precipitation  Decreased solubility  Biological change :  Loss of function Increased digestibility by proteolytic enzymes 8/17/2021 32 Dr Ifat, dept of Biochemistry, DMC
  • 33. 8/17/2021 33 Dr Ifat, dept of Biochemistry, DMC
  • 34.  Source of energy  Formation of cytoskeleton (Flexible structural framework for cells / tissues)  Provides :  Mechanical support: By structural protein like collagen, elastin  Defense against infection: By antibody like immunoglobulin  Helps in:  Muscle contraction : By contractile protein like actin, myosin  Coagulation : By clotting factors 8/17/2021 34 Dr Ifat, Dept of Biochemistry, DMC  Acts as:  Vehicle for transport of diff molecules like hormones, drugs, vitamins etc  Buffer
  • 35.  Promotes:  Catalytic function by enzymes  Hormonal functions by hormones  Plasma proteins maintain COP of plasma to maintain blood volume 8/17/2021 35 Dr Ifat, Dept of Biochemistry, DMC  Storage, expression & transmission of genetic information by nucleoprotein
  • 36. 8/17/2021 36 Dr Ifat, Dept of Biochemistry, DMC