3.7 Types of Proteins
First review @October 5, 2023
Practise Q's Done
two main types of proteins are fibrous and globular proteins
Globular proteins
compact, water soluble, usually spherical in shape
they are formed when proteins fold so that the hydrophobic R-groups don’t interact with
the aqueous environment but the hydrophilic R-groups do, hence their ability to dissolve
in water
their solubility in water is essential for regulating many essential life processes
Insulin is an example of a globular protein
involved in the regulation of blood-glucose levels, needs to be soluble so that it can
be transported into the bloodstream
has a precise shape so it can fit into the receptors on plasma membranes
Conjugated proteins
globular proteins that contain a prosthetic group (proteins without prosthetic groups
are simple proteins)
to form prosthetic groups, lipids and carbohydrates can combine with proteins to
form lipoproteins or glycoproteins
metal ions and molecules from vitamins can also form prosthetic groups
an example of a prosthetic group is a haem group because they contain iron II
cations
catalase and haemoglobin contain haem groups
Haemoglobin
red pigment within erythrocytes that binds to oxygen
quaternary protein made from two alpha helix proteins, two beta pleated sheet
proteins and four haem groups (one for each subunit)
3.7 Types of Proteins 1
First review @October 5, 2023
Practise Q's Done
two main types of proteins are fibrous and globular proteins
Globular proteins
compact, water soluble, usually spherical in shape
they are formed when proteins fold so that the hydrophobic R-groups don’t interact with
the aqueous environment but the hydrophilic R-groups do, hence their ability to dissolve
in water
their solubility in water is essential for regulating many essential life processes
Insulin is an example of a globular protein
involved in the regulation of blood-glucose levels, needs to be soluble so that it can
be transported into the bloodstream
has a precise shape so it can fit into the receptors on plasma membranes
Conjugated proteins
globular proteins that contain a prosthetic group (proteins without prosthetic groups
are simple proteins)
to form prosthetic groups, lipids and carbohydrates can combine with proteins to
form lipoproteins or glycoproteins
metal ions and molecules from vitamins can also form prosthetic groups
an example of a prosthetic group is a haem group because they contain iron II
cations
catalase and haemoglobin contain haem groups
Haemoglobin
red pigment within erythrocytes that binds to oxygen
quaternary protein made from two alpha helix proteins, two beta pleated sheet
proteins and four haem groups (one for each subunit)
3.7 Types of Proteins 1
