Fructoselysine

Fructoselysine is an Amadori adduct of glucose to lysine.
It breaks down into furosine on acid-catalysed hydrolysis. "E. coli" breaks it down using the enzymes fructoselysine-6-kinase and fructoselysine 6-phosphate deglycase into glucose 6-phosphate and lysine, a set of enzymes located on the "frl" (fructoselysine) operon.