What are proteins?
Proteins are the building blocks of life. They are
vital for the growth of cells and tissue repair.
They are instrumental in everything that an
Functions of Proteins
•Offer structural support
•Helps in storage
•Helps in transportation
•Helps in intercellular signaling
•Aid in movement
•Helps in metabolism
•Provides defense against foreign materials
Do you know????
Humans have tens of thousands of different
proteins, each with their own structure and
They are the most complex molecules known till
Basics of proteins
•Proteins have a three dimensional shape
•Protein polymers are constructed from amino
•Protein polymers are called polypeptides
Structure of Proteins
The function of proteins depends on its structure.
The function depends on its ability to recognize
and bind to some other molecule.
Levels of protein structure
There are four levels of protein structure
Primary structure level
The primary structure level of a protein is its
unique sequence of amino acid. This structure is
generally determined by inherited genetic
Secondary structure level
The secondary structure level of protein is the
result of hydrogen bonds at regular intervals
along the polypeptide backbone.
Tertiary structure level
Tertiary structure level of a protein depends on a
number of interactions among the different
groups and the polypeptide group.
Quarternary structure level
Quarternary structure results from the
combination of two or more polypeptide subunits.