DIFFERENTIATE FIBROUS AND GLOBULAR PROTEIN

 Protein Structure
Several level of protein structure
 1.   Primary structure – sequence of amino acid.
 2.   Secondary structure – local structure.
 3.   Tertiary structure – overall 3D shape of protein.
 4.   Quarternary structure – subunit organization

Tertiary structure - 2 examples of tertiary structures are fibrous and globular protein.

Fibrous protein vs Globular protein

Fibrous	Globular
Called as scleroproteins. Elongated strand-like structures and are usually in the form of rods or wires.	Called as spheroproteins owing to their shape. Spherical in shape and has the property of forming colloids with water.
It insoluble in water, weak acids and weak bases but soluble in strong acids and alkalis	It soluble in water, acids and bases
The peptide chains are bound together by strong intermolecular hydrogen bonds in fibrous proteins.	The peptide chains are bound together by weak intermolecular hydrogen bonds in globular proteins.
Scleroproteins do not denature easily.	Spheroproteins denature easily.
Fibrous proteins have primary and secondary structures.	Globular are made up of not only primary, secondary but also tertiary and occasionally quaternary structure.
Fibrous proteins are made up of repetitive continuations of one small unit but multiple times.	Globular proteins consist of straight chains of secondary structures which abruptly join polypeptide chains and change directions.
Function Needed for the formation of tough structures like connective tissue, tendons and fibers of the muscle. Play important structural roles in nature	Function They are uses to form enzymes, cellular messengers and amino acids which are basic building blocks of all proteins. Responsible for transportation of vital nutrients like oxygen through haemoglobin.
Examples Collagen - major component of all our connective tissue Fibroin - use to produce silk by silkworms and webs of spiders. Keratin - formation of hair and wool	Examples  Haemoglobin - used to carry oxygen and carbon dioxide (in blood) through out the whole body cells. Myoglobin - carry oxygen molecules to muscle tissue.