Open AccessPurification and properties of an NADPH‐dependent dihydroxyacetone reductase from Phycomyces spores
Author(s) -
Laere André
Publication year - 1985
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1985.tb01114.x
Subject(s) - phycomyces , dihydroxyacetone , phycomyces blakesleeanus , glycerol , glyceraldehyde , biochemistry , dihydroxyacetone phosphate , enzyme , oxidoreductase , arabitol , biology , mycelium , spore , chemistry , dehydrogenase , botany , mutant , gene , xylitol , fermentation
A glycerol:NADP + 2‐oxidoreductase was purified to homogeneity from Phycomyces blakesleeanus sporangiospores. The enzyme had an M r of 34 000–39 000 and consisted of a single polypeptide. It had a pH optimum between 6–6.5 and a K m of 3.9 mM for dihydroxyacetone. The reverse reaction had a pH optimum of 9.4 and a K m for glycerol of more than 2 M. The enzyme was completely specific for NADPH ( K m = 0.01 mM) or NADP + ( K m = 0.17 mM) and greatly preferred dihydroxyacetone over glyceraldehyde as substrate. Besides glycerol, l ‐arabitol and mesoerythritol were also oxidized by the enzyme. It was inhibited by ionic strengths in excess of 100 mM and is probably involved in the synthesis of glycerol during early spore germination.