Presentation on Protein and
Amino Acid
Fibrous and Globular Protein
Fibrous Protein
• Proteins that is arranged in a long chain.
• Typically water-insoluble, due to having the
hydrophobic Amino Acids sticking out from
the protein.
• Most are Structural Protein, also acts as
storage protein for energy and ions
Examples
• Collagen: Main structural protein in the
human body, found in various parts of the
human body, including muscles
• Fibroin: Protein present in silk produced by
some types of incest, including spiders
• Keratin: Main structural protein in the outer
layer of the human skin, also present in the
nail and hair
Globular Protein
• Spherical shaped protein
• Induced through the protein’s tertiary
structure (Geometry of the protein)
• More water soluble than Fibrous Protein, due
to hydrophobic amino acid facing inward
towards the center while hydrophilic amino
acid facing outward
Examples
• Hemoglobin: Transport Oxygen around the
human body
• Actin: Used in muscle contraction
• Antibodies (Immunoglobulin): Used in the
Immune system to fight of diseases
Polar and non-polar Amino
Acid(AA)
Peptide
Polar Amino Acid
• Peptides that have a Polar side chain
• May include Oxygen or other polar functional
group (etc. OH group) in the side chain
• Includes AA like Tyrosine, Threonine, Serine
and Asparagine
Non-polar AA
• Peptides that have a non-polar side chain
• Mainly includes only carbon and hydrogen in
the side chain
• Includes AA like Alanine, Phenylalanine, Valine
and Glycine.
Charged AA
• Amino Acids that have a side chain that can be
charged
• Depend on the pH of the solution and the pKa
of the AA
• Includes AA like Arginine, Aspartic acid,
Glutamic acid and Lysine