Forensic Chemistry - The Different Uses of Proteins

Distinguish between protein used for structural purposes and the uses of proteins as enzymes

Proteins

is known as the most abundant biomolecule having its building blocks called amino acids
can be classified in terms of its shape, function and composition.

Based on Shape:

- Globular (spherical) – Generally soluble in water
  Example: Hemoglobin
- Fibrous (thread-like) – Stretched, twisted and generally insoluble in water

Example: Collagen

Based on Composition:

Simple – pure protein
Example: Globulin, Albumin
Conjugated – protein with non-protein substances
Example: Glycoproteins, Lipoproteins

Based on Biological Function:

a. Transport Proteins

b. Nutrient and Storage Proteins

c. Contractile Proteins

d. Defense Proteins

e. Regulatory Proteins

f. Enzymes

– serve as catalyst of biological reactions

– generally globular and water soluble

-contain active site where catalysis occurs

– all enzymes are proteins except for ribozymes

– can be classified as oxidoreductases, transferases, hydrolases, lyases, isomerases and ligases

Examples: Insulin , Hemoglobin, Lipase, Pepsin, Hexokinase, Pyruvate decarboxylase

g. Structural Proteins

– stingy, physically tough and insoluble in water which work for structural support

Example: Keratin in skin, fingernails and hair