Protein Flashcards
Protein made of
In some proteins
After water
Protein are polymers of
— used in formation of protein
Protein amino acid type
C,H ,O,N,S
I,Fe ,P,
Proteins are most abundant component of cell [ 10 - 15%]
Macromolecules of amino acid
20 types of amino acid
Essential
Non essential
Essential amino acids
I isoleucine
L leucine
L lysin
P. Phenylalanine
M methionire
T tryptophan
Go to
V valine
T threonine
Semiessential
Acidic amino acids
Basic amino acids
Neutral
Argentine, histidine
Glutamic aced, aspertic acid
Lysis, Argentine, histidine
Valine, rest 15 amino acid
Amino acids are
Alpha amino acids are
Four substituent group occupying the four valency
Hydrogen amino acid having
Methyl group
Hydroxyl method
Organic compounds containing an amino group and an acidic group as substituents on same carbon ie alpha carbon
Substituted methanes
Hydrogen, carbonyl group, amino group, a variable group designated asR group
Glycine
Alanine
Serine
Each Amino acid is
Isoelectric point
Amphoteric compound because it contains both acidic -COOH and an alkaline group
-NH2
Is that point of ph at which amino acids have both positive / negative charge in equal amount
Is specific value of ph at which amino acids move neither towards cathode nor anode
Amino a acids join by __________ to form protein
Also known as
Properties of protein depend on
Variation in amino acid
Peptide bond
Amide bond
Sequence of amino acids and configuration of protein molecules
Depend on side group
Primary protein
________ chain of amino acid linked by ________
Soluble. / insoluble in water
Stable / unstable
Primary structure of protein
Linear chain of amino acid linked by peptide bond
Insoluble in water
Most unstable type of protein
The sequence of amino acids i.e the positional information in protein which is the first amino acid which is second and so on
Secondary protein bond
Structure
Alpha - helix
Bonding
E.g
Peptide bond, hydrogen bond
Coiled
Right handed rotation of spirally coiled chain
Has Intramolecular hydrogen bonding ie b/w 2 amino acid of same chain
Keratin, myosin, tropomyosin
Beta - helix sheath structure
Protein molecule has
Bonding
Eg
Keratin
Is , due to
Beta plated sheet
Zig - zag structure
Two er more polypeptide chains are held together by intermolecular bond
Eg fibroin [ silk]
Alpha Felix eg
Fibrous, tough, resistance to digestion, scleroprotein
Abundance of cysteine amino acids in its structure
Tertiary protein
_______ have highly folded tertions structure
Soluble / Insoluble in water
Bonds
Strongest bond in protein
Second strongest bond
B/ w Hydrophobic side
Gives us a 3 dimensional view of protein
Globular protein
Soluble in water colloidal solution
Peptide bond
Hydrogen band
Disulphide bond
Hydrophobic bond eg aromatic amino acids
Ionic bond asparatic , lysine
Majority of protein enzyme in protoplasm
Exhibit tertiary structure which is absolutely necessary for biological activities of protein
Quaternary structure
Eg
It is most
Two or more poly peptide chain of tertiary structure unite by different type of bonds
Haemoglobin → made up of 4 poly peptide chain= 2 alpha chains, 2 beta chains
Insulin → made up of 2 poly peptide chain = l alpha chain,l beta chain
Stable structure
Order of stability
Disulphide bond
Ionic bond
Quaternary > tertiary > secondary > primary
Form b/w -SH [ Thiol group) of amino acid [ cysteine ]
Stabilise tertiary
Oppositely charged side chains eg aspartic acid, lysine
Denaturation of protein
During ( destroyed)
But
Change in temp / ph may lead to loss of functional structure of protein
Secondary, tertiary, quaternary structure of protein may be destroyed
Primary structure is not destroyed as peptide bonds ere not broken
Chemical analysis used part
Grind it in
Fraction base
Two fractions
Piece of liver or vegetable
Trichloroacetic acid CL3CCOOH using a mortar and pestle
Molecular weight
Filtrate / acid soluble
Retentate / acid insoluble