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Hemoglobin
Hemoglobin (haemoglobin, Hb or Hgb) is a protein containing iron that facilitates the transportation of oxygen in red blood cells. Almost all vertebrates contain hemoglobin, with the sole exception of the fish family Channichthyidae. Hemoglobin in the blood carries oxygen from the respiratory organs (lungs or gills) to the other tissues of the body, where it releases the oxygen to enable aerobic respiration which powers an animal's metabolism. A healthy human has 12to 20grams of hemoglobin in every 100mL of blood. Hemoglobin is a metalloprotein, a chromoprotein, and a globulin. In mammals, hemoglobin makes up about 96% of a red blood cell's dry matter, dry weight (excluding water), and around 35% of the total weight (including water). Hemoglobin has an oxygen-binding capacity of 1.34mL of O2 per gram, which increases the total blood oxygen capacity seventy-fold compared to dissolved oxygen in blood plasma alone. The mammalian hemoglobin molecule can bind and transport up to four ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HBA2
Hemoglobin, alpha 2 also known as ''HBA2'' is a gene that in humans codes for the alpha globin chain of hemoglobin. Function The human alpha globin gene cluster is located on chromosome 16 and spans about 30 kb, including seven alpha like globin genes and pseudogenes: 5'- Hemoglobin subunit zeta, HBZ - HBZP1 - Mu hemoglobin, HBM - HBAP1 - HBA2 - HBA1 - HBQ1 -3'. The HBA2 (α2) and Hemoglobin, alpha 1, HBA1 (α1) coding sequences are identical. These genes differ slightly over the 5' untranslated regions and the introns, but they differ significantly over the 3' untranslated regions. Protein Two alpha chains plus two beta chains constitute Hemoglobin A, HbA, which in normal adult life accounts for about 97% of the total hemoglobin; alpha chains combine with delta chains to constitute Hemoglobin A2, HbA-2, which with Fetal hemoglobin, HbF (fetal hemoglobin), composed of alpha and gamma chains, make up the remaining 3% of adult hemoglobin. Clinical significance Alpha-thala ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HBA1
Hemoglobin subunit alpha, Hemoglobin, alpha 1, is a hemoglobin protein that in humans is encoded by the ''HBA1'' gene. Gene The human alpha globin gene cluster located on chromosome 16 spans about 30 kb and includes seven loci: 5'- zeta - pseudozeta - mu - pseudoalpha-1 - alpha-2 - alpha-1 - theta - 3'. The alpha-2 (HBA2) and alpha-1 (HBA1; this gene) coding sequences are identical. These genes differ slightly over the 5' untranslated regions and the introns, but they differ significantly over the 3' untranslated regions. Protein Two alpha chains plus two beta chains constitute HbA, which in normal adult life accounts for about 97% of the total hemoglobin; alpha chains combine with delta chains to constitute HbA-2, which with fetal hemoglobin (HbF), composed of alpha and gamma chains, make up the remaining 3% of adult hemoglobin. Clinical significance Alpha thalassemias result from deletions of each of the alpha genes as well as deletions of both HBA2 Hemoglobin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood
Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood is composed of blood cells suspended in blood plasma. Plasma, which constitutes 55% of blood fluid, is mostly water (92% by volume), and contains proteins, glucose, mineral ions, and hormones. The blood cells are mainly red blood cells (erythrocytes), white blood cells (leukocytes), and (in mammals) platelets (thrombocytes). The most abundant cells are red blood cells. These contain hemoglobin, which facilitates oxygen transport by reversibly binding to it, increasing its solubility. Jawed vertebrates have an adaptive immune system, based largely on white blood cells. White blood cells help to resist infections and parasites. Platelets are important in the clotting of blood. Blood is circulated around the body through blood vessels by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heme Protein
A hemeprotein (or haemprotein; also hemoprotein or haemoprotein), or heme protein, is a protein that contains a heme prosthetic group. They are a very large class of metalloproteins. The heme group confers functionality, which can include oxygen carrying, oxygen reduction, electron transfer, and other processes. Heme is bound to the protein either covalently or noncovalently or both. The heme consists of iron cation bound at the center of the conjugate base of the porphyrin, as well as other ligands attached to the "axial sites" of the iron. The porphyrin ring is a planar dianionic, tetradentate ligand. The iron is typically Fe2+ or Fe3+. One or two ligands are attached at the axial sites. The porphyrin ring has four nitrogen atoms that bind to the iron, leaving two other coordination positions of the iron available for bonding to the histidine of the protein and a divalent atom. Hemeproteins probably evolved to incorporate the iron atom contained within the protoporphyri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Oxygen Capacity
Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood is composed of blood cells suspended in blood plasma. Plasma, which constitutes 55% of blood fluid, is mostly water (92% by volume), and contains proteins, glucose, mineral ions, and hormones. The blood cells are mainly red blood cells (erythrocytes), white blood cells (leukocytes), and (in mammals) platelets (thrombocytes). The most abundant cells are red blood cells. These contain hemoglobin, which facilitates oxygen transport by reversibly binding to it, increasing its solubility. Jawed vertebrates have an adaptive immune system, based largely on white blood cells. White blood cells help to resist infections and parasites. Platelets are important in the clotting of blood. Blood is circulated around the body through blood vessels by the pump ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Globin
The globins are a superfamily of heme-containing globular proteins, involved in binding and/or transporting oxygen. These proteins all incorporate the globin fold, a series of eight alpha helical segments. Two prominent members include myoglobin and hemoglobin. Both of these proteins reversibly bind oxygen via a heme prosthetic group. They are widely distributed in many organisms. Structure Globin superfamily members share a common three-dimensional fold. This 'globin fold' typically consists of eight alpha helices, although some proteins have additional helix extensions at their termini. Since the globin fold contains only helices, it is classified as an all-alpha protein fold. The globin fold is found in its namesake globin families as well as in phycocyanins. The globin fold was thus the first protein fold discovered (myoglobin was the first protein whose structure was solved). Helix packaging The eight helices of the globin fold core share significant nonlocal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbaminohemoglobin
Carbaminohemoglobin (carbaminohaemoglobin BrE) (CO2Hb, also known as carbhemoglobin and carbohemoglobin) is a Chemical compound, compound of hemoglobin and carbon dioxide, and is one of the forms in which carbon dioxide exists in the blood. In blood, 23% of carbon dioxide is carried this way, while 70% is converted into bicarbonate by carbonic anhydrase and then carried in plasma, and 7% carried as free CO2, dissolved in plasma. Structure The structure of carbaminohemoglobin can be described as the binding of carbon dioxide to the amino groups of the globin chains of hemoglobin. This occurs at the N-terminals of the globin chains and at the amino sidebranches of arginine and lysine residues. The process of carbon dioxide binding to hemoglobin is generally known as carbamino formation. This is the source from where the protein gets its name, as it is a combination of carbamino and hemoglobin. Function One of the primary functions of carbaminohemoglobin is to enable the trans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Blood Cell
Red blood cells (RBCs), referred to as erythrocytes (, with -''cyte'' translated as 'cell' in modern usage) in academia and medical publishing, also known as red cells, erythroid cells, and rarely haematids, are the most common type of blood cell and the vertebrate's principal means of delivering oxygen () to the body tissue (biology), tissues—via blood flow through the circulatory system. Erythrocytes take up oxygen in the lungs, or in fish the gills, and release it into tissues while squeezing through the body's capillary, capillaries. The cytoplasm of a red blood cell is rich in hemoglobin (Hb), an iron-containing biomolecule that can bind oxygen and is responsible for the red color of the cells and the blood. Each human red blood cell contains approximately 270 million hemoglobin molecules. The cell membrane is composed of proteins and lipids, and this structure provides properties essential for physiological Cell (biology), cell function such as erythrocyte deformabil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's outer and inner core. It is the fourth most abundant element in the Earth's crust, being mainly deposited by meteorites in its metallic state. Extracting usable metal from iron ores requires kilns or furnaces capable of reaching , about 500 °C (900 °F) higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BC and the use of iron tools and weapons began to displace copper alloys – in some regions, only around 1200 BC. That event is considered the transition from the Bronze Age to the Iron Age. In the modern world, iron alloys, such as steel, stainless steel, cast iron and special steels, are by far the most common industrial metals, due to their mechan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heme
Heme (American English), or haem (Commonwealth English, both pronounced /Help:IPA/English, hi:m/ ), is a ring-shaped iron-containing molecule that commonly serves as a Ligand (biochemistry), ligand of various proteins, more notably as a Prosthetic group, component of hemoglobin, which is necessary to bind oxygen in the bloodstream. It is composed of four pyrrole rings with 2 Vinyl group, vinyl and 2 propionic acid side chains. Heme is biosynthesized in both the bone marrow and the liver. Heme plays a critical role in multiple different redox reactions in mammals, due to its ability to carry the oxygen molecule. Reactions include oxidative metabolism (cytochrome c oxidase, succinate dehydrogenase), xenobiotic detoxification via cytochrome P450 pathways (including Drug metabolism, metabolism of some drugs), gas sensing (Guanylate cyclase, guanyl cyclases, nitric oxide synthase), and microRNA processing (DGCR8). Heme is a coordination complex "consisting of an iron ion coordinated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Channichthyidae
The crocodile icefish or white-blooded fish comprise a family (biology), family (Channichthyidae) of notothenioid fishes, fish found in the Southern Ocean around Antarctica. They are the only known vertebrates to lack hemoglobin in their blood as adults. Icefish populations are known to reside in the Atlantic Ocean, Atlantic and Indian Ocean, Indian sectors of the Southern Ocean, as well as the continental shelf waters surrounding Antarctica. Water temperatures in these regions remain relatively stable, generally ranging from . One icefish, ''Champsocephalus esox,'' is distributed north of the Antarctic Convergence, Antarctic Polar Frontal Zone. At least 16 species of crocodile icefish are currently recognized, although eight additional species have been proposed for the icefish genus ''Channichthys.'' In February 2021, scientists discovered and documented a breeding colony of ''Neopagetopsis ionah'' icefish estimated to have 60 million active nests across an area of approximately ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metalloprotein
Metalloprotein is a generic term for a protein that contains a metal ion cofactor. A large proportion of all proteins are part of this category. For instance, at least 1000 human proteins (out of ~20,000) contain zinc-binding protein domains although there may be up to 3000 human zinc metalloproteins. Abundance It is estimated that approximately half of all proteins contain a metal. In another estimate, about one quarter to one third of all proteins are proposed to require metals to carry out their functions. Thus, metalloproteins have many different functions in cells, such as storage and transport of proteins, enzymes and signal transduction proteins, or infectious diseases. The abundance of metal binding proteins may be inherent to the amino acids that proteins use, as even artificial proteins without evolutionary history will readily bind metals. Most metals in the human body are bound to proteins. For instance, the relatively high concentration of iron in the human body ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
