The Quaternary Structure of Protein

1. “A Structure Level Some Proteins
Have”

2. The quaternary structure found in some
proteins results from interactions between two
or more polypeptide chains — interactions that
are usually the same as those that give rise to
the tertiary structure

3. •The Quaternary Structure of Protein is consist of two
or more polypeptide chains and are held together by
noncovalent interactions (hydrogen bonds, ionic bonds,
and hydrophobic interactions)
•Subunits may either function independently of each
other, or may work cooperatively, as in hemoglobin, in
which the binding of oxygen to one subunit of the
tetramer increases the attraction of the other subunits
for oxygen.

4. Many proteins are made up of multiple polypeptide
chains, often referred to as protein subunits.
The quaternary structure refers to how these
protein subunits interact with each other and arrange
themselves to form a larger combined protein complex.
The final shape of the protein complex is once again
stabilized by various interactions, including hydrogen-
bonding, disulfide-bridges and salt bridges.

6. Hemoglobin | Haemoglobin

7. •Hemoglobin, abbreviated Hb or Hgb, is the iron
containing oxygen-transport metalloprotein in the red
blood cells of all vertebrates as well as the tissues of
some invertebrates.
•Hemoglobin in the blood carries oxygen from the
respiratory organs (lungs or gills) to the rest of the body
(tissues). There it releases the oxygen to permit aerobic
respiration to provide energy to power the functions of
the organism in the process called metabolism.

8. DNA Polymerases

9. The DNA polymerases are enzymes that
create DNA molecules by assembling nucleotides, the
building blocks of DNA. These enzymes are essential
to DNA replication and usually work in pairs to create two
identical DNA strands from a single original DNA
molecule.
Every time a cell divides, DNA polymerase is required to
help duplicate the cell’s DNA, so that a copy of the
original DNA molecule can be passed to each of the
daughter cells. In this way, genetic information is
transmitted from generation to generation.