In enzymology, D-lysopine dehydrogenase () is an enzyme that catalyzes the chemical reaction
The three substrates of this enzyme are D-lysopine, oxidised nicotinamide adenine dinucleotide phosphate (NADP<sup>+</sup>), and water. Its products are L-lysine, reduced NADPH, pyruvic acid, and a proton.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is N2-(D-1-carboxyethyl)-L-lysine:NADP+ oxidoreductase (L-lysine-forming). Other names in common use include D-lysopine synthase, lysopine dehydrogenase, D(+)-lysopine dehydrogenase, 2-N-(D-1-carboxyethyl)-L-lysine:NADP+ oxidoreductase, and (L-lysine-forming). This enzyme participates in lysine degradation.
D-lysopine is an opine, a compound found in plant crown gall tumors or hairy root tumors produced by pathogenic bacteria of the genus Agrobacterium and Rhizobium.