Proteins
• Proteins are the most abundant biomolecules of the living system.
• Chief sources of proteins are milk, cheese, pulses, peanuts, fish, meat,
etc.
• They occur in every part of the body and form the fundamental basis
of structure and functions of life.
• They are also required for growth and maintenance of body.
• The word protein is derived from Greek word, “proteios” which
means primary or of prime importance.
• Proteins are polypeptides.
[Peptide == a compound consisting of two or more amino acids linked
in a chain].
• Proteins are linear chains of amino acids linked by peptide bonds.
• Each protein is a polymer of amino acids.
[Monomer == a molecule that can be bonded to other identical
molecules to form a polymer].
• Dietary proteins are the source of essential amino acids.
• Therefore, amino acids can be essential or non-essential.
Non-Essential Amino Acids == Amino Acids that our body can make].
[Essential Amino Acids == We get them through our diet/food].
• Collagen is the most abundant protein in animal world.
• Ribulose bisphosphate Carboxylase-Oxygenase (RuBisCO) is the most
abundant protein in the whole of the biosphere.
