Accepted name: D-arabinitol dehydrogenase (NADP+)
Reaction: (1) D-arabinitol + NADP+ = D-xylulose + NADPH + H+
(2) D-arabinitol + NADP+ = D-ribulose + NADPH + H+
Other name(s): NADP+-dependent D-arabitol dehydrogenase; ARD1p; D-arabitol dehydrogenase 1
Systematic name: D-arabinitol:NADP+ oxidoreductase
Comments: The enzyme from the rust fungus Uromyces fabae can use D-arabinitol and D-mannitol as substrates in the forward direction and D-xylulose, D-ribulose and, to a lesser extent, D-fructose as substrates in the reverse direction. This enzyme carries out the reactions of both EC, D-arabinitol 4-dehydrogenase and EC, D-arabinitol 2-dehydrogenase, but unlike them, uses NADP+ rather than NAD+ as cofactor. D-Arabinitol is capable of quenching reactive oxygen species involved in defense reactions of the host plant.
1.  Link, T., Lohaus, G., Heiser, I., Mendgen, K., Hahn, M. and Voegele, R.T. Characterization of a novel NADP+-dependent D-arabitol dehydrogenase from the plant pathogen Uromyces fabae. Biochem. J. 389 (2005) 289–295. [PMID: 15796718]
[EC created 2005]