Allysine

From WikiMD's Wellness Encyclopedia

Allysine


Allysine is an amino acid that plays a critical role in the biosynthesis and cross-linking of collagen and elastin, which are essential components of the connective tissue in animals. It is not one of the proteinogenic amino acids that are directly incorporated into proteins during translation. Instead, allysine is formed by the post-translational modification of lysine, another amino acid, within collagen and elastin molecules. This modification is catalyzed by the enzyme lysyl oxidase, which oxidizes the ε-amino group of lysine to form allysine.

Biosynthesis[edit | edit source]

The biosynthesis of allysine begins with the enzyme lysyl oxidase acting on lysine residues in collagen and elastin precursors. Lysyl oxidase is a copper-dependent enzyme that oxidizes the ε-amino group of lysine to an aldehyde group, resulting in the formation of allysine. This reaction is crucial for the subsequent cross-linking steps that give collagen and elastin their structural integrity and elasticity.

Function[edit | edit source]

Allysine plays a pivotal role in the formation of cross-links between individual collagen and elastin molecules. After its formation, allysine can react with other amino acid residues, such as lysine or hydroxylysine, to form various types of covalent bonds. These cross-links are essential for the stability and function of the extracellular matrix, contributing to the tensile strength of tissues and the elasticity of blood vessels.

Clinical Significance[edit | edit source]

Alterations in the activity of lysyl oxidase, and consequently in the formation of allysine, can lead to various connective tissue disorders. For example, a deficiency in lysyl oxidase activity can result in weakened connective tissue, leading to conditions such as Ehlers-Danlos syndrome and Marfan syndrome. On the other hand, excessive cross-linking due to increased lysyl oxidase activity has been associated with fibrotic diseases and the stiffening of arterial walls in atherosclerosis.

See Also[edit | edit source]

WikiMD
Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD

Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD

WikiMD's Wellness Encyclopedia

Let Food Be Thy Medicine
Medicine Thy Food - Hippocrates

Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.

Contributors: Prab R. Tumpati, MD