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 (prō′tēn′, -tē-ĭn)
Any of a group of complex organic macromolecules that contain carbon, hydrogen, oxygen, nitrogen, and usually sulfur and are composed of one or more chains of amino acids. Proteins are fundamental components of all living cells and include many substances, such as enzymes, hormones, and antibodies, that are necessary for the proper functioning of an organism. They are essential in the diet of animals for the growth and repair of tissue and can be obtained from foods such as meat, fish, eggs, milk, and legumes.

[French protéine, from Late Greek prōteios, of the first quality, from Greek prōtos, first; see per in Indo-European roots.]

pro′tein·a′ceous (prōt′n-ā′shəs, prō′tē-nā′-), pro·tein′ic (prō-tē′nĭk), pro·tein′ous (prō-tē′nəs) adj.
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.
References in periodicals archive ?
It is highly proteinous and can easily fill up your stomach.
According to the results of this study, the renal effects of diabetes were evident, especially in proximal tubular injury (proteinous material accumulation) with a significant reduction occurring in histopathologic total cellular injury scores.
Accumulation of dense proteinous material in the form of casts was observed beginning in the subcortical area of the proximal, distal and collector tubule lumens and extending to the renal pelvis.
Transbronchial lung biopsy was performed, and histology (Figures 4 and 5) showed air space consolidation with fibrinous exudation and polymorph and macrophage infiltration, along with polypoidal proteinous layer in the alveolar spaces composed of granulation tissue, with alveolar septa showing moderately dense chronic inflammatory infiltrates (Masson bodies), all were suggestive of cryptogenic organizing pneumonia (BOOP).
Kadivar, "Preparation and characterization of proteinous film from lentil (Lens culinaris)" Food Research International, vol.
For the removal of proteinous matter, the extract was precipitated with 80% acetone at 0AdegC and incubated at 20AdegC, for 24 h.
Behind the female's bottomless appetite is the extraordinary size of her egg case, a frothy proteinous mass studded with up to 400 eggs that can amount to half her body weight.
(16) They will typically have white proteinous deposits in two rings on the front of the crystalline lens--one forms when the pupil is dilated in dim illumination and the other smaller ring results from deposits when the pupil is more constricted in daylight.
The presence of nitrogen in water was caused by the decomposition of proteinous compounds in waste water (Voznoya, 2008).