website was produced as an assignment for an undergraduate course at
3D Structure of Hemoglobin
Hemoglobin is the protein primarily responsible for providing cells
much-needed oxygen throughout the human body. This macromolecule
consists of an iron-containing heme group that, when in the lungs,
binds to oxygen and then proceed to carry its oxygen content to all the
cells in the body.
Reset and spin this Hemoglobin molecule.
Hemoglobin is a tetramer consisting of four polypeptide
chains. The two α-globin
chains and two β-globin chains are all alpha helices, which
can be seen here. Collectively, these secondary structures provide the
hemoglobin with its quaternary form.
The two α-globin
chains are displayed here. Notice that these chains are similar in
length and size.
β-globin chains are displayed here. Notice that these chains are
similar in length and size. Does there seem to be any differences
between the α-globin
chains and β-globin chains in terms of size and length?
Here we can see how the heme group is bound to one of
the chains of the hemoglobin. There are four such of these heme groups
in every hemoglobin. Notice the large, ring-like structure of the heme
group, including the labelled iron atom that is reponsible for oxygen
binding. Also notice the location of the distal and proximal histidine
chains, which are responsible for stabilizing the heme group. The
distal histidine helps ensure that the heme group bind to oxygen and
not only carbon waste (Boyer, 2006). Because of its highly useful
nature, this specific region is highly conserved.
Boyer R, et
al. 2006. Myglobin & Hemoglobin. http://www3.interscience.wiley.com:8100/legacy/college/boyer/0471661791/structure/HbMb/hbmb.htm.
Hua's Home Page
Please send suggestions, questions, or
comments to firstname.lastname@example.org
Biology Home Page
© Copyright 2010 Department of Biology, Davidson College,
Davidson, NC 28036
Send comments, questions, and suggestions to: email@example.com