Allysine (All)

Allysine is a derivative of lysine, used in the production of elastin and collagen. It is produced by the actions of the enzyme lysyl oxidase in the extracellular matrix and is essential in the crosslink formation that stabilizes collagen and elastin. Allysine is a very important crosslink precursor in connective tissue proteins. The reactions of Phthalyl-Allysine-p-Nitrobenzylester, which is a suitable compound to investigate the reactions of the aldehyde group in vitro. Crosslinked compounds are synthesized by mixing suitable stoichiometric amounts of Phthalyl-Allysine-p-Nitrobenzylester and nucleophiles in aqueous organic solvents. The results are compared with the reaction pathways which have been proposed for crosslink synthesis in vivo. The first step in normal cross-linking in elastin is the formation of alpha-aminoadipic-delta-semialdehyde, allysine, through oxidative deamination of specific peptidyl lysine by the enzyme lysyl oxidase.