Yarrowia lipolytica dehydrogenase/reductase: An enzyme tolerant for lipophilic compounds and carbohydrate substrates

Yarrowia lipolytica short chain dehydrogenase/reductase (YlSDR) was expressed in Escherichia coli, purified and characterized in vitro. The substrate scope for YlSDR mediated oxidation was investigated with alcohols and unprotected carbohydrates spectrophotometrically, revealing a preference for secondary compared to primary alcohols. In reduction direction, YlSDR was highly active on ribulose and fructose, suggesting that the enzyme is a mannitol-2-dehydrogenase. In order to explore substrate tolerance especially for space-demanding, lipophilic protecting groups, 5-O-trityl-d-ribitol and 5-O-trityl-α,β-d-ribose were investigated as substrates: YlSDR oxidized 5-O-trityl-d-ribitol and 5-O-trityl-α,β-d-ribose and reduced the latter at the expense of NADP(H).