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protamine
pro·ta·mine P0611400 (prō′tə-mēn′, -mĭn) also pro·ta·min (-mĭn)n. Any of a group of arginine-rich proteins that bind to and package DNA in the sperm nucleus. Protamines are used in long-acting formulations of insulin and to neutralize the anticoagulant effects of heparin.protamine (ˈprəʊtəˌmiːn) n (Biochemistry) any of a group of basic simple proteins that occur, in association with nucleic acids, in the sperm of some fish[C19: from German: see proto-, amine]prot•a•mine (ˈproʊ təˌmin, prɒˈtæm ɪn)
n. any of a group of arginine-rich, strongly basic proteins that are not coagulated by heat. [1870–75] Thesaurus| Noun | 1. | protamine - a simple protein found in fish sperm; rich in arginine; simpler in composition than globulin or albumin; counteracts the anticoagulant effect of heparinsimple protein - a protein that yields only amino acids when hydrolyzed |
Protamine
protamine[′prōd·ə‚mēn] (biochemistry) Any of the simple proteins that are combined with nucleic acid in the sperm of certain fish, and that upon hydrolysis yield basic amino acids; used in medicine to control hemorrhage, and in the preparation of an insulin form to control diabetes. Protamine a protein of low molecular weight that occurs in the nuclei of spermatozoa in fish and birds. Its molecular weight ranges from 4,000 to 12,000. The basic properties of protamines are determined by their characteristically high content of basic amino acids, especially arginine (70–80 percent). Protamines are readily soluble in water and in acid and neutral media. They are precipitated by alkalies and do not denature when heated. The protamines that have been studied are mainly those found in mature fish spermatozoa, where they constitute a fraction of the basic protein but nearly the entire nuclear protein. The amino-acid composition of protamines is specific for each species of fish. In cell nuclei, protamines, like histones, are associated with deoxyribonucleic acids to form nucleoprotamines. X-ray diffraction analysis has shown that the protamine chain is the third strand coiled around the DNA double helix. Protamines form salts in the presence of acids and complexes with acid proteins; in medicine, the slightly soluble complex of protamine and insulin is used to prolong the effectiveness of the latter. protamine
protamine [pro´tah-min] any of a class of simple proteins, soluble in water, not coagulated by heat, and precipitated from aqueous solution by addition of alcohol. Protamines neutralize heparin, and protamine sulfate is used as an antidote in heparin overdosage, administered intravenously.pro·ta·mine (prō'tă-mēn, -min), Any of a class of proteins, highly basic because rich in l-arginine and simpler in constitution than the albumins and globulins, etc., found in fish spermatozoa in combination with nucleic acid; the protamines have a histonelike function and are present in mammalian sperm; neutralizes anticoagulant action of heparin; used in the preparation of several long-acting insulin preparations.protamine (prō′tə-mēn′, -mĭn) also protamin (-mĭn)n. Any of a group of arginine-rich proteins that bind to and package DNA in the sperm nucleus. Protamines are used in long-acting formulations of insulin and to neutralize the anticoagulant effects of heparin.pro·ta·mine (prō'tă-mēn) Any of a class of proteins found in fish sperms in combination with nucleic acid; neutralizes anticoagulant action of heparin. protamine
Related to protamine: protamine insulinWords related to protaminenoun a simple protein found in fish spermRelated Words |