- an essential amino acid, C3H3N2CH2CH(NH2)COOH, that is a constituent of proteins and is important as the iron-binding site in hemoglobin. Abbreviation: His; Symbol: H
Also his·ti·din [his-ti-din] /ˈhɪs tɪ dɪn/.
Origin of histidine
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- a nonessential amino acid that occurs in most proteins: a precursor of histamine
Word Origin and History for histidine
complex amino acid, 1896, from German histidin; see histo- + chemical suffix -idine.
Online Etymology Dictionary, © 2010 Douglas Harper
- An amino acid that is essential for tissue growth and repair.
- An amino acid that is essential for children but not for adults. Chemical formula: C6H9N3O2.
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