Zusammenfassung der Ressource
Globular and fibrous
proteins
- In globular proteins the
polypeptide chain is folded into a
compact spherical shape.
- Fibrous proteins do not fold up
into a ball shape but remain as
longs chains.
- The globular proteins are
soluble due to the hydrophilic
side chains that project from
the out side of the molecules
and are therefore important in
metabolic reactions.
- The fibrous proteins are insoluble (hydrophobic) and
important structural molecules. Several
polypeptide chains can be cross-linked
for additional strength.
- Haemoglobin is a globular protein. it
acts as an oxygen transport
molecule. It is made up of four
polypeptide chains, each is
associated with an iron-containing
haem group (grey). Oxygen attaches
to the iron with the haem group.
Because the protein is associated
with another chemical group it is
called a conjugated protein.
- Collagen is a fibrous protein. Three
polypeptide chains wind around each other to
form a rope-like strand held together by
hydrogen bonds between the chains. Each
strand cross-links to other strands to produce
a molecule with tremendous strength.
- They are all polypeptides
- Both encoded by DNA
- identical length
- Varied length
- Structural role
- Functional and structural role