Synthesis of lysinonorleucine and mass spectrometric analysis of lysinonorleucine and merodesmosine in bovine ligament and eggshell membrane.

Elastin is an important extracellular matrix protein that contributes to the elasticity of cells, tissues, and organs. Although crosslinking amino acids such as desmosine and isodesmosine have been identified in elastin, details regarding the structure remain unclear. In this study, an elastin crosslinker, lysinonorleucine, was chemically synthesized and detected in hydrolyzed bovine ligament and eggshell membrane samples utilizing tandem mass spectrometry. Merodesmosine, another crosslinker of elastin, was also measured in the same samples using the same analytical method. The resulting data should aid in the elucidating the crosslinking structure of elastin and eggshell membranes.