Blood oxygenator hemoglobin, oxygen binding

The most conspicuous use of iron in biological systems is in our blood, where the erythrocytes are filled with the oxygen-binding protein hemoglobin. The red color of blood is due to the iron atom bound to the heme group in hemoglobin. Similar heme-bound iron atoms are present in a number of proteins involved in electron-transfer reactions, notably cytochromes. A chemically more sophisticated use of iron is found in an enzyme, ribo nucleotide reductase, that catalyzes the conversion of ribonucleotides to deoxyribonucleotides, an important step in the synthesis of the building blocks of DNA. 

Diphosphoglycerate A compound in red blood cells that affects oxygen binding to and release from hemoglobin. 

This reaction is catalyzed by carbonic anhydrase, an enzyme particularly abundant in erythrocytes. Carbon dioxide is not very soluble in aqueous solution, and bubbles of C02 would form in the tissues and blood if it were not converted to bicarbonate. As you can see from the equation, the hydration of C02 results in an increase in the H+ concentration (a decrease in pH) in the tissues. The binding of oxygen by hemoglobin is profoundly influenced by pH and C02 concentration, so the interconversion of C02 and bicarbonate is of great importance to the regulation of oxygen binding and release in the blood. 

It has been found that vitamin K analogues possess an ability to insert themselves into the oxygen-binding cleft of hemoglobin. This may result m hemolysis (dissolution of red blood corpuscles with liberation of their hemoglobin),... 

Figure 9.3 The iron-containing heme group on hemoglobin that binds with molecular oxygen and enables red blood cells to carry oxygen to tissues.

The compound 2,3-bisphosphoglycerate (BPG, also known as 2,3-diphosphoglycerate or DPG) is produced within the red blood cell of many animal species, and acts to modify the oxygen binding affinity of hemoglobin ... 

Hemoglobin (abbreviated Hb) is a protein that is responsible for the transport of oxygen in the blood of mammals. Each hemoglobin molecule contains four iron atoms that are the binding sites for 02 molecules. The oxygen binding is pH-dependent. The relevant equilibrium reaction is as follows ... 

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