Category: Proteins
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Vitellin is essential in the fertilization process, and embryonic development in egg-laying organisms
Vitellin is a protein found in the egg yolk. It is a phosphoprotein. Vitellin is a generic name for major of many yolk proteins. Vitellin has been known since the 1900s. The periodic acid-Schiff method and Sudan black B dye was used to help determine that Vitellin is a glycolipoprotein because it stained positive when tested. This protein was…
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Protein phosphorylation was first reported in 1906
Protein phosphorylation is a reversible post-translational modification of proteins in which an amino acid residue is phosphorylated by a protein kinase by the addition of a covalently bound phosphate group. Phosphorylation alters the structural conformation of a protein, causing it to become activated, deactivated, or otherwise modifying its function. Approximately 13,000 human proteins have sites that are phosphorylated. The reverse reaction of phosphorylation is called dephosphorylation, and is catalyzed by…
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Ku is a dimeric protein complex that binds to DNA double-strand break ends and is required for the non-homologous end joining (NHEJ) pathway of DNA repair
Ku is evolutionarily conserved from bacteria to humans. The ancestral bacterial Ku is a homodimer (two copies of the same protein bound to each other).[2] Eukaryotic Ku is a heterodimer of two polypeptides, Ku70 (XRCC6) and Ku80 (XRCC5), so named because the molecular weight of the human Ku proteins is around 70 kDa and 80 kDa. The two Ku subunits form a basket-shaped structure that threads onto…
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Ku70
Ku70 is a protein that, in humans, is encoded by the XRCC6 gene.[5][6] Function Together, Ku70 and Ku80 make up the Ku heterodimer, which binds to DNA double-strand break ends and is required for the non-homologous end joining (NHEJ) pathway of DNA repair. It is also required for V(D)J recombination, which utilizes the NHEJ pathway to promote antigen diversity in the mammalian immune system. In addition to its role in NHEJ, Ku…
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Ku80
Ku80 is a protein that, in humans, is encoded by the XRCC5 gene.[5] Together, Ku70 and Ku80 make up the Ku heterodimer, which binds to DNA double-strand break ends and is required for the non-homologous end joining (NHEJ) pathway of DNA repair. It is also required for V(D)J recombination, which utilizes the NHEJ pathway to promote antigen diversity in the mammalian immune system. In addition to its role in NHEJ, Ku is required…
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Fibroin is an insoluble protein present in silk produced by numerous insects
Fibroin is an insoluble protein present in silk produced by numerous insects, such as the larvae of Bombyx mori, and other moth genera such as Antheraea, Cricula, Samia and Gonometa. Silk in its raw state consists of two main proteins, sericin and fibroin, with a glue-like layer of sericin coating two singular filaments of fibroin called brins. BRIN AND BAVE (BRIN) One of the radiating sticks of a fan.…
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Ferrochelatase catalyses the eighth and terminal step in the biosynthesis of heme, converting protoporphyrin IX into heme B
Protoporphyrin ferrochelatase (EC 4.98.1.1, formerly EC 4.99.1.1, or ferrochelatase; systematic name protoheme ferro-lyase (protoporphyrin-forming)) is an enzyme encoded by the FECH gene in humans. Ferrochelatase catalyses the eighth and terminal step in the biosynthesis of heme, converting protoporphyrin IX into heme B. It catalyses the reaction: protoheme + 2 H+ = protoporphyrin + Fe2+ Function Ferrochelatase catalyzes the insertion of ferrous iron into protoporphyrin IX in the heme biosynthesis…
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Ceruloplasmin carries more than 95% of the total copper in healthy human plasma and in addition plays a role in iron metabolism. It was first described in 1948.
Ceruloplasmin (or caeruloplasmin) is a ferroxidase enzyme that in humans is encoded by the CP gene. Ceruloplasmin is the major copper-carrying protein in the blood, and in addition plays a role in iron metabolism. It was first described in 1948. Another protein, hephaestin, is noted for its homology to ceruloplasmin, and also participates in iron and probably copper metabolism. Function Ceruloplasmin (CP) is an enzyme (EC 1.16.3.1) synthesized…
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Follistatin also known as activin-binding protein and formerly known as FSH-suppressing protein (FSP)
Follistatin also known as activin-binding protein is a protein that in humans is encoded by the FST gene. Follistatin is an autocrine glycoprotein that is expressed in nearly all tissues of higher animals. Its primary function is the binding and bioneutralization of members of the TGF-β superfamily, with a particular focus on activin, a paracrine hormone. An earlier name for the same protein was FSH-suppressing protein (FSP). At the time of its…
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Sterol carrier proteins (aka nonspecific lipid transfer proteins)
These proteins are different from plant nonspecific lipid transfer proteins but structurally similar to small proteins of unknown function from Thermus thermophilus. This domain is involved in binding sterols. The human sterol carrier protein 2 (SCP2) is a basic protein that is believed to participate in the intracellular transport of cholesterol and various other lipids. Human…
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What is Immunoprecipitation (IP)?
Immunoprecipitation (IP) is a technique used to enrich protein antigens from a complex mixture using specific antibodies. To carry out an IP, antibodies must be coupled to a solid substrate, such as agarose resin or magnetic beads, to allow for purification of the target antigens. Immunoprecipitation (IP) is the technique of precipitating a protein antigen out of solution using an antibody that…
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Erepsin
Erepsin is a mixture of enzymes contained in a protein fraction found in the intestinal juices that digest peptones into amino acids. It is produced and secreted by the intestinal glands in the ileum and the pancreas, but it is also found widely in other cells. It is, however, a term now rarely used in scientific literature as more precise terms are preferred. History Erepsin was discovered at the…
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Digestive enzymes
Digestive enzymes are a group of enzymes that break down polymeric macromolecules into their smaller building blocks, in order to facilitate their absorption into the cells of the body. Digestive enzymes are found in the digestive tracts of animals (including humans) and in the tracts of carnivorous plants, where they aid in the digestion of food, as well as inside cells,…
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Digestive enzymes
In carnivorous plants digestive enzymes and acids break down insects and in some plants small animals. In some plants the leaf collapses on the prey to increase contact, others have a small vessel of digestive liquid. Then digestion fluids are used to digest the prey to get at the needed nitrates and phosphorus. The absorption of the needed nutrients are usually more efficient…
