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pro·ta·mine(prō′tə-mēn′, -mĭn) also pro·ta·min (-mĭn)
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.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.