Involved in oxygen transport from the lung to the various peripheral tissues. LVV-hemorphin-7 potentiates the activity of bradykinin, causing a decrease in blood pressure. Functions as an endogenous inhibitor of enkephalin-degrading enzymes such as DPP3, and as a selective antagonist of the P2RX3 receptor which is involved in pain signaling, these properties implicate it as a regulator of pain and inflammation. Heterotetramer of two alpha chains and two beta chains in adult hemoglobin A (HbA). Heterotetramer of two zeta chains and two beta chains in hemoglobin Portland-2, detected in fetuses and neonates with homozygous alpha-thalassemia. Red blood cells. Glucose reacts non-enzymatically with the N-terminus of the beta chain to form a stable ketoamine linkage. This takes place slowly and continuously throughout the 120-day life span of the red blood cell. The rate of glycation is increased in patients with diabetes mellitus. S-nitrosylated; a nitric oxide group is first bound to Fe(2+) and then transferred to Cys-94 to allow capture of O(2). Acetylated on Lys-60, Lys-83 and Lys-145 upon aspirin exposure. Genetic variations in HBB are involved in resistance to malaria [MIM:611162]. Hemoglobin S (Hb S), which at homozygosity is responsible for sickle cell anemia, is not associated with any clinical abnormality when heterozygous. At heterozygosity, Hb S confers an increase in protection from life-threatening malaria. Additional variants conferring resistance against severe malaria are hemoglobin C (Hb C) and hemoglobin E (Hb E). The disease may be caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. One molecule of 2,3-bisphosphoglycerate can bind to two beta chains per hemoglobin tetramer. Belongs to the globin family. The modification form of Leu-142 is subject of controversy and could be the artifactual result of sample handling. It is unclear if hemoglobin Beckman (Hb Beckman) is defined by p.Ala136Glu or p.Ala136Asp. Hb Beckman has been originally identified by reverse phase-HPLC and tandem mass spectrometry, and has been reported as variant p.Ala136Glu (Ref.140). Subsequently, variant p.Ala136Asp has been reported based on HBB gene complete sequencing results (PubMed:19453576). Variant p.Ala136Asp has also been detected by mass spectrometry (PubMed:26209877). Although the name Hb Beckman is currently used for variant p.Ala136Asp, it cannot be ruled out that Hb Beckman is indeed variant p.Ala136Glu (PubMed:19453576). Human hemoglobin variants and thalassemias Hemoglobin entry