Describe the quaternary structure of insulin, including disulfide bonding. (h) In solution, two
molecules of insulin form a hydrogen bonded pair. What is the new quaternary structure? NOTE:
this is an active, blood-soluble form of the molecule. (i) In the presence of divalent cations, such
as Zn2+, six molecules of insulin form a new, non-water-soluble mass. What is the quaternary
structure of this new protein, which is much less clinically useful than the first one?
Solution
INSULIN: The lack of insulin causes a form of diabetes.Insulin is a hormone made by
pancreas by the islets of Langerhans, which regulates the amount of glucose in the blood.
Quarternary structure of insulin:Hormone insulin consisting of two polypepetide chains.Due to
interaction between hydrophobic surfaces insulin can form into granules consisting of
hexamers.Insulin can form into dimers.doughnut shaped form is the one in which insulin is
stored in the beta cells and secreted through blood stream.
The presence of zn2+ in granules to the capacity of insulin and its precursorsto bind cation with a
high affinity.zn2+ promotes the formation of insulin and makes crystallization and
precipitation.In the presence of divalent cations the new protein formed is a hexamer itself have
six subunits..
Describe the quaternary structure of insulin, including disulfide bo.pdf
1. Describe the quaternary structure of insulin, including disulfide bonding. (h) In solution, two
molecules of insulin form a hydrogen bonded pair. What is the new quaternary structure? NOTE:
this is an active, blood-soluble form of the molecule. (i) In the presence of divalent cations, such
as Zn2+, six molecules of insulin form a new, non-water-soluble mass. What is the quaternary
structure of this new protein, which is much less clinically useful than the first one?
Solution
INSULIN: The lack of insulin causes a form of diabetes.Insulin is a hormone made by
pancreas by the islets of Langerhans, which regulates the amount of glucose in the blood.
Quarternary structure of insulin:Hormone insulin consisting of two polypepetide chains.Due to
interaction between hydrophobic surfaces insulin can form into granules consisting of
hexamers.Insulin can form into dimers.doughnut shaped form is the one in which insulin is
stored in the beta cells and secreted through blood stream.
The presence of zn2+ in granules to the capacity of insulin and its precursorsto bind cation with a
high affinity.zn2+ promotes the formation of insulin and makes crystallization and
precipitation.In the presence of divalent cations the new protein formed is a hexamer itself have
six subunits.
