protamine pro·ta·mine (prō'tə-mēn', -mĭn) or pro·ta·min (-mĭn)
Any of a group of simple proteins found in fish sperm that are strongly basic, are soluble in water, are not coagulated by heat, and yield chiefly arginine upon hydrolysis. In purified form, they are used in a long-acting formulation of insulin and to neutralize the anticoagulant effects of heparin.
simple alkaline protein usually occurring in combination with a nucleic acid as a nucleoprotein. In the 1870s Johann Friedrich Miescher discovered a protamine, salmine, in the sperm of salmon. Other typical protamines include sturine, from sturgeon, and clupeine, from herring sperm. The drug protamine sulfate, prepared from the sperm of various fishes, is used as an antidote to overdoses of the anticoagulant heparin.
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