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amino acid

American  
[uh-mee-noh as-id] / əˈmi noʊ ˈæs ɪd /

noun

Biochemistry.
  1. any of a class of organic compounds that contains at least one amino group, –NH 2 , and one carboxyl group, –COOH: the alpha-amino acids, RCH(NH2 )COOH, are the building blocks from which proteins are constructed.


amino acid British  

noun

  1. any of a group of organic compounds containing one or more amino groups, -NH 2 , and one or more carboxyl groups, -COOH. The alpha-amino acids RCH(NH 2 )COOH (where R is either hydrogen or an organic group) are the component molecules of proteins; some can be synthesized in the body ( nonessential amino acids ) and others cannot and are thus essential components of the diet ( essential amino acids )

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

amino acid Scientific  
  1. Any of a large number of compounds found in living cells that contain carbon, oxygen, hydrogen, and nitrogen, and join together to form proteins. Amino acids contain a basic amino group (NH 2) and an acidic carboxyl group (COOH), both attached to the same carbon atom. Since the carboxyl group has a proton available for binding with the electrons of another atom, and the amino group has electrons available for binding with a proton from another atom, the amino acid behaves as an acid and a base simultaneously. Twenty of the naturally occurring amino acids are the building blocks of proteins, which they form by being connected to each other in chains. Eight of those twenty, called essential amino acids, cannot be synthesized in the cells of humans and must be consumed as part of the diet. The remaining twelve are nonessential amino acids.


Etymology

Origin of amino acid

First recorded in 1895–1900

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Further experiments showed that a specific amino acid, cysteine 272 in the cytoplasmic region of PD-L1, is essential for this modification.

From Science Daily

Peptides are short chains made when individual amino acids link together.

From Science Daily

Many dairy farms rely on expensive supplements, including added fats and amino acids, to fine-tune cow nutrition.

From Science Daily

Bamboo also provides essential amino acids, along with minerals such as selenium and potassium.

From Science Daily

With his longtime producing partner Gary Krieg, they gravitated toward researchers solving the problem of “protein folding,” figuring out how to predict the 3-D shape of proteins from a chain of amino acids.

From The Wall Street Journal