Hemoglobin: Difference between revisions

'''Hemoglobin''' is a protein that is located in [[red blood cells]], which binds [[oxygen]] from the [[lungs]] to deliver to the organs and tissues.<ref name=medicine>[http://www.medicinenet.com/hemoglobin/article.htm Hemoglobin]  Siamak Nabili. MedicineNet.com </ref> Hemoglobin is made of two similar proteins, alpha and beta, that are combined together.<ref name=sick>[http://sickle.bwh.harvard.edu/hemoglobin.html An Overview of Hemoglobin] Maureen Okam. Information Center for Sickle Cell and Thalassemic Disorder </ref> Since each alpha and beta has its own two protein molecules, Hemoglobin actually consists of four different protein molecules, also called globulin chains. Usually, hemoglobin molecule in the normal adult includes two alpha-globulin chains and two beta-globulin chains. On the other hand, in infants, the hemoglobin molecule contains two alpha chains and two gamma chains. As the infant matures, two gamma chains are changed to two beta chains. Each different globulin chain has the heme molecule, which is iron that carries the oxygen and carbon dioxide in blood. Because of the presence of the heme molecule, blood is seemed a red color. Also, hemoglobin helps to build the shape of the red blood cells. <ref> [http://www.medterms.com/script/main/art.asp?articlekey=15738 Definition of Hemoglobin] MedicineNet.com </ref> <ref> [http://www.thefreedictionary.com/hemoglobin+A Hemoglobin] The Free Dictionary </ref>

In 1840, at Leipzig University in Germany, the hemoglobin protein that carries oxygen was discovered by Hünefeld first. In 1851, in his articles about diluting red blood cells with a solvent such as pure water (H₂O) or alcohol, Otto Funke, a German physiologist, explained "growing hemoglobin crystals." A few years later, Felix Hoppe-Seyler, a German physiologist and chemist, discovered the binding of oxygen to erythrocytes that is one of hemoglobin's functions. This discovery is also called the process of creating the compound oxyhemoglobin. After studying hemoglobin in crystalline form, Hoppe-Seyler discovered that hemoglobin contains iron. <ref> [http://www.britannica.com/EBchecked/topic/271586/Ernst-Felix-Immanuel-Hoppe-Seyler Ernst Felix Hoppe-Seyler] Encyclopædia Britannica Online </ref> In 1959, using X-ray crystallography, Max Perutz, an Austrian-British molecular biologist, established the molecular structure of hemoglobin. His great discovery helped him win the Nobel Prize for Chemistry in 1962. <ref> [http://www.answers.com/topic/max-perutz Max Perutz] Answers.com </ref> <ref> [http://en.wikipedia.org/wiki/Hemoglobin#Research_history Hemoglobin] Wikipedia.org </ref>

Due to problems and mutations in globin gene regulation, there are two kinds of hemoglobins that are produce, normal and abnormal hemoglobins.

Usually, a low hemoglobin causes to have anemia. However, there are more causes of low hemoglobin besides anemia;

People who smoke or live at high altitudes can have higher hemoglobin levels than those who do not smoke. Dehydration is the main cause that produces a high hemoglobin. However, unlike other serious diseases, people can lower their high hemoglobin levels easily.  

A porphyrin, known as a heterocyclic ring, is located at the center of the molecule and has an iron atom, which helps oxygens begin binding. An iron that consists porphyrin is called a heme. It is also part of the prosthetic group of hemoglobin, myoglobin, and the cytochromes. <ref> [http://www.rpi.edu/dept/bcbp/molbiochem/MBWeb/mb2/part1/heme.htm Synthesis of Heme] Joyce J. Diwan. Biochemistry of Metabolism </ref> Globin is the protein that protects the heme molecule from any other dangers. It is also called a globular protein. A single unit of hemoglobin includes a heme that is attached to a globular protein. <ref name=bioche> [http://themedicalbiochemistrypage.org/hemoglobin-myoglobin.html Hemoglobin and Myoglobin ] Michael W. King. The Medical Biochemistry Page </ref> Hemoglobin synthesis requires the collaboration of heme and globin. In the mitochondria and the [[cytosol]] of immature red blood cells, the heme part is combined with a series of steps. On the other hand, the globin protein parts are incorporated with ribosomes in the cytosol. From the proerythroblast to the reticulocyte in the bone marrow, they keep producing hemoglobins in the cell. The nucleus is then removed from mammalian red blood cells. This happens only in humans but not in other species. Although the nucleus is disappeared in red blood cells, residual ribosomal RNA keeps combining and producing hemoglobin until the reticulocyte loses its RNA as soon as it enters the vasculature.