Either of two organic compounds. Alpha-alanine is one of the nonessential amino acids, found in most proteins and particularly abundant in fibroin, the protein in silk. It is used in research and as a dietary supplement. Beta-alanine is a naturally occurring amino acid not found in proteins. It is an important constituent of the vitamin pantothenic acid and is used in its synthesis, as well as in biochemical research, electroplating, and organic synthesis.
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Good sources of alanine include:
Alanine is most commonly produced by reductive amination of pyruvate. Because transamination reactions are readily reversible and pyruvate pervasive, alanine can be easily formed and thus has close links to metabolic pathways such as glycolysis, gluconeogenesis, and the citric acid cycle. It also arises together with lactate and generates glucose from protein via the alanine cycle.
Glucose-alanine cycle enables pyruvate and glutamate to be removed from muscle and find their ways to liver. Glucose is able to be regenerated from pyruvate and returned to muscle. The energetic burden of gluconeogenesis is thus imposed on the liver instead of the muscle. All available ATP in muscle is devoted to muscle contraction.
This property of alanine is used in dosimetric measurements in radiotherapy. When normal alanine is irradiated, the radiation causes certain alanine molecules to become free radicals, and, as these radicals are stable, the free radical content can later be measured in order to find out how much radiation the alanine was exposed to. In this way, one can be assured that complex radiotherapy treatment plans will deliver the intended pattern of radiation dose.
ALT1-encoded alanine aminotransferase plays a central role in the metabolism of alanine in Saccharomyces cerevisiae.(Report)
Apr 01, 2009; Introduction Pathways for the biosynthesis and catabolism of amino acids have been thoroughly studied in Saccharomyces...
Purification and preliminary crystallization of alanine racemase from Streptococcus pneumoniae.(Research article)(Report)
May 17, 2007; Authors: Ulrich Strych ; Milya Davlieva ; Joseph P Longtin ; Eileen L Murphy ; Hookang Im ; Michael J Benedik ;...