191 12.73 Iron Functions
As we talked about in the previous subsection, there are 3 primary functional iron subcompartments.
1. Hemoglobin
2. Myoglobin
3. Iron-containing enzymes
Hemoglobin contains heme that is responsible for red blood cells’ red color. Hemoglobin carries oxygen to tissues. The function of hemoglobin can be seen in the link below.
| Web Link
–Hemoglobin |
Myoglobin is similar to hemoglobin in that it can bind oxygen. However, instead of being found in blood, it is found in muscle. The color of meat products is a result of the state that myoglobin is in, as shown in the link below.
| Web Link
–Myoglobin & Meat Color |
There are a number of enzymes that use iron as a cofactor. We’ve already talked about two in this class.
Iron is a cofactor for the antioxidant enzyme, catalase, that converts hydrogen peroxide to water, as shown below.
Iron is also a cofactor for proline and lysyl hydroxylases that are important in collagen cross-linking. This will be discussed further in the vitamin C section. The function of these enzymes is shown below.
Heme iron is also found in cytochromes, like cytochrome c in the electron transport chain as shown below1.
References & Links
1. Gropper SS, Smith JL, Groff JL. (2008) Advanced nutrition and human metabolism. Belmont, CA: Wadsworth Publishing.
2. http://wikidoc.org/index.php/File:ETC.PNG
Links
Hemoglobin – http://www.nlm.nih.gov/medlineplus/ency/imagepages/19510.htm
Myoglobin & Meat Color – http://meatisneat.files.wordpress.com/2009/09/slide11.jpg